2024-03-29T10:13:24Z
https://www.fracturae.com/index.php/index/oai
oai:ojs.www.fracturae.com:article/889
2013-07-21T11:03:23Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/889
2013-07-21T11:03:23Z
Metallurgical Science and Tecnology
Vol. 1 No. 1 (1983)
Ductile fracture nucleation ahead of sharp cracks
Firrao, D.
Roberti, R.
2013-07-21
url:https://www.fracturae.com/index.php/MST/article/view/889
en_US
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oai:ojs.www.fracturae.com:article/890
2013-07-21T11:03:23Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/890
2013-07-21T11:03:23Z
Metallurgical Science and Tecnology
Vol. 1 No. 1 (1983)
Moulding of iron castings with evaporative polystyrene foam patterns immersed in loose sand: prospects and problems
Goria, C.A.
Del Gaudio, G.
Caironi, G.
Silva, G.
Selli, M.
2013-07-21
url:https://www.fracturae.com/index.php/MST/article/view/890
en_US
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oai:ojs.www.fracturae.com:article/891
2013-07-21T11:03:23Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/891
2013-07-21T11:03:23Z
Metallurgical Science and Tecnology
Vol. 1 No. 1 (1983)
Thermal analysis in the light alloys foundry
Marino, F.
Medana, R.
2013-07-21
url:https://www.fracturae.com/index.php/MST/article/view/891
en_US
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oai:ojs.www.fracturae.com:article/892
2013-09-06T11:56:17Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/892
2013-09-06T11:56:17Z
Metallurgical Science and Tecnology
Vol. 1 No. 2 (1983)
Constitution and corrosion resistance of phosphate protective coatings
Acquarone, Giuseppina
Angelini, Emma
Bianco, Paolo
Grassi, Gianfranca
2013-07-21
url:https://www.fracturae.com/index.php/MST/article/view/892
en_US
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oai:ojs.www.fracturae.com:article/893
2013-09-06T11:56:18Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/893
2013-09-06T11:56:18Z
Metallurgical Science and Tecnology
Vol. 1 No. 2 (1983)
Solid state equilibria in the Cr-Fe-B system at the temperature of 1373 K
Gianoglio, Carlo
Pradelli, Giorgio
Vallino, Mario
2013-07-21
url:https://www.fracturae.com/index.php/MST/article/view/893
en_US
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oai:ojs.www.fracturae.com:article/895
2013-09-06T11:56:27Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/895
2013-09-06T11:56:27Z
Metallurgical Science and Tecnology
Vol. 2 No. 1 (1984)
An opproisal of the energy crdck zero (ECo) test in the evaluation of tempered martensite embrittlement (TME)
CAVALLINI, M.
BALLARIN, M.
WAGNER, V.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/895
en_US
Tempered martensite embrittlement (TME) was investigated in an electroslag remelted (ESR) aeronautical grade SAE 4340 steel. The Charpy - Vimpact, plane strarn fracture toughness (K1") and energy crack zero (ECo) tests were employed to evaluate the reduced toughness of 300"C ascompared with 200"C-tempered specimens after fracture in the temperature range from - 70'C to + 150"C. The ECo and Charpy - V results werecomparable. The K1. test, however, failed to detect TME, even though a fatigue precracked specimen was used as in the ECo test. Thisdiscrepancy between the two tests is attributed to the different rnfluence of a microtough zone a few pm thick at the crack tip. Caution is thereforeadvised in the conversion of ECo values to their K6 equivalents.
oai:ojs.www.fracturae.com:article/896
2013-09-06T11:56:28Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/896
2013-09-06T11:56:28Z
Metallurgical Science and Tecnology
Vol. 2 No. 1 (1984)
Mechanical instabilities of metals Temperature changes during deforrnotion are indices of fundamental processes
BOTTANI, CARLO E.
CAGLIOTI, GIUSEPPE
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/896
en_US
ln the general context of the non-.linear thermodynamics of irreversible phenomena, the.thermoelasioptastic between transition occurring at the boundary the thermoelastic and thermoplastic régimes of deformation br m"ta,ttic À"terials can be seén as a bifurcation point. This non-equilibrium phase transformation is detected by measuing lhe rcmperature changes in a sample unaergoiij àefo,r;;i;;, since these are indices of fundamental processes" initial cooiingunderaÚiabaticconditionsdueíothethirÀiaelastice"fferítLorakitini,'185' )issuddentyfollowedbyarise il.r?!!?,::yn cau2_e-( bv entropy próduction in the highty irreversitte tnerÀiItastìc regime beyoìna tÀe niriícation. tnermal emtsston (l E) at and.beyond yielding can also be usefully exploited, tógether,ilith acoústic emiisiotn-if required, in the investigation of thermodynamic transformations or mechanlcal instabilities durin'g *nirn m,ecn'anìiat *ork is converted into thermal energy, as in creep, fatigue and fracture, for example.
oai:ojs.www.fracturae.com:article/897
2013-09-06T11:56:29Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/897
2013-09-06T11:56:29Z
Metallurgical Science and Tecnology
Vol. 2 No. 1 (1984)
îhe influence of carbide morphology on the upper-shelf fracture toughness of carbon steels
Firrao, D.
Anzalone, S.A.
BEGLEY, J.A.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/897
en_US
UNI C 15, C 45, and C 85 pla.in carbon steel specimens were prepared for J-integrat testing in the furnace-annealed, normalized, conditions and spheroidized at an upper-shelf temperature of 225'C. Furnace-anniealed and normiafizea steéts aóÀur" o-iturú1, regards to tougihness,' ùh,"r"u, spheroidized steels exhibit higher levels of toughness and ductitity. Since fracture in low and medium C lamblar péarlite steelé occurred predominantly in the ferrite, fracture toughnesies were associated wtth the distribution of pearlite colonies withiin the ferrite and the resultingcontained plastic deformation, which grows as the average free ferrite parth decreases. Also J1. values in sphetroidized structures resulteddepended mainlv on the mean free path between carbidés with a decrease in spacing resiliiií iiti*éiti|giÈness values.
oai:ojs.www.fracturae.com:article/899
2013-09-06T12:04:07Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/899
2013-09-06T12:04:07Z
Metallurgical Science and Tecnology
Vol. 2 No. 2 (1984)
Review of surface factors in stress corrosion cracking of alloys
Bombara, G.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/899
en_US
From morphological observations of typical cracks in a susceptible system of wide practical interest, a number of distinctive features is pointed out and a comprehensive definition drawn for stress-corrosion cracking. Electrochemical mechanisms of crack nucleation at passive or relatively inert surfaces and subsequent subcritical propagation of nucleated cracks are outlined according to the most accepted models. Besides the number of surface factors involved in both stages, special theoretical consideration is given to the direct role played by surface energy in a growing crack. This is in relation to the highly active state of the metal at the crack tip (i. e. high tendency to release surface atoms) in front of the passive state of side surfaces. In the light of the mechanisms outlined, basic techniques are described for the experimental study of stress-corrosion cracking susceptibility.
oai:ojs.www.fracturae.com:article/900
2013-09-06T12:04:27Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/900
2013-09-06T12:04:27Z
Metallurgical Science and Tecnology
Vol. 2 No. 3 (1984)
An application of the J-integral engineering approach to blunt notch specimens
Roberti, R.
Ghidini, A.
Firrao, D.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/900
en_US
The influence of notch root radius on crack growth resistance behaviour (J-Resistance curve) of a C-Mn structural steel was investigated by fracture mechanics experiments with three-point bending specimens. J-R Curves was determined by the multiple specimen technique and it was found that, while the J-integral at initiation is differently affected by small and large notch root radii, the tearing modulus, on the contrary, is independent on notch root radius.The J-R curves have also been obtained by applying the estimation scheme developed by Kumar, German and Shih to evaluate the crack driving force; the estimation scheme was also utilized to evaluate the loading behaviour of both cracked and blunt notched specimens. The comparison between predictions and experimental results has generally shown a good accordance, thus extending the applicability of the J-integral engineering approach to blunt notch specimens.
oai:ojs.www.fracturae.com:article/901
2013-09-06T12:04:27Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/901
2013-09-06T12:04:27Z
Metallurgical Science and Tecnology
Vol. 2 No. 3 (1984)
Fatigue crack growth in heat-affected zone of butt-welded AISI316 steam pipes
Cusolito, R.
Mandorini, V.
D’Angelo, D.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/901
en_US
The aim of this paper is to report the methodology and results of fatigue crack propagation tests at high temperature on an actual TP 316 H stainless steel heat-affected zone. Some metallographical investigations are also reported linking the effect of local microstructures with the variable crack propagation rate.Finally, the residual life assessment of a cracked steampipe is briefly analysed as a typical application of the Fracture Mechanics approach at high temperature to check the structural stability of power plant components.
oai:ojs.www.fracturae.com:article/902
2013-09-06T12:04:27Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/902
2013-09-06T12:04:27Z
Metallurgical Science and Tecnology
Vol. 2 No. 3 (1984)
Temperature variations around the crack tip during a fracture test
Beghi, M.
Bottaimi, Ce.
Caglioti, G.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/902
en_US
Preliminary results are reported of the temperature variations in a fatigue pre-cracked compact tension specimen ofAISI 316, subjected to a uniformly increasing cross-head displacement. The temperature variations in the regions surrounding the crack tip are sensed by three point-like thermistors.At the thermoelastic-plastic instability the load vs. time characteristic exhibits a barely perceptible kink. Conversely, the initial thermoelastic cooling is followed by a sudden temperature rise near the crack tip and a delayed, smoother rise at greater distances. This experimental procedure, based on " thermal emission " allows one to identify with precision the formation and development of the plastic zone
oai:ojs.www.fracturae.com:article/903
2013-09-06T12:04:50Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/903
2013-09-06T12:04:50Z
Metallurgical Science and Tecnology
Vol. 3 No. 1 (1985)
Distribution of chromium and nickel between the phases present in the borided layer of alloy steels
Badini, C.
Gianoglio, C.
Pradelli, G.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/903
en_US
The preferential distribution of transition elements in the borided layer consisting of phases derived from the borides FeB (rhombic) and Fe2B (tetragonal) has been verified using commercial steels containing chromium and nickel (UNI UX 100 Cr 13, UNI X8Cr 17 and UNI X8 CrNi 1808). Bonding treatment was carried out at 900° C with powders enriched in KBF4 and CB4. The average content of the alloying elements was determined using the microanalysis of areas of dimensions comparable with those of the single phase layers.It was found that chromium diffuses from the parent metal into the borided layer and is distributed preferentially in the phase which is more rich in boron, as we have already discovered in investigation of the two phase field [(Fe,Cr)2B + (Fe,Cr)B] of the system Fe-Cr-B; nickel on the other hand tends to diffuse from the external layer into the bulk of the metal and the rhombic phase becomes depleted in this element in comparison with the tetragonal phase. These conclusions are in agreement with the generally valid observation which we have made in ternary systems between boron and pairs of transition metals as a result of which the element having the high atomic number is preferentially inserted into the phase which is less rich in boron in the distribution of the above mentioned metals between borides in equilibrium in the two phase zone. An intermediate zone between the borided layers and the bulk of the metal which is particularly rich in carbon, and, in the case of UNIX 8 CrNi 1808 steel only, nickel also, has been observed in all the steels examined
oai:ojs.www.fracturae.com:article/904
2013-09-06T12:04:50Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/904
2013-09-06T12:04:50Z
Metallurgical Science and Tecnology
Vol. 3 No. 1 (1985)
On the nature of the so-called "ghost lines" in stand-cast steel
Colombo, R.L.
Sandrone, L.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/904
en_US
One of the defects which show up in strand-cast steel and persist in the rolled shapes and forgings, irrespective of the degree of hot plastic deformation, is the so-called "ghost lines ". Because of their appearance on magnetic inspection of finite parts and macrographic etching, they are still termed "Innenrisse " (internal cracks) in Germany, and sometimes considered-objectionable. In this study it is shown that they consist of segregated metal, enriched with sulphur and alloy elements, with the exception of carbon and nickel. Their influence on the mechanical behaviour of the steel, at least as long as their amount does not substantially exceed that present in our material is of little, if any, importance.
oai:ojs.www.fracturae.com:article/905
2013-09-06T12:04:50Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/905
2013-09-06T12:04:50Z
Metallurgical Science and Tecnology
Vol. 3 No. 1 (1985)
Prospects for metals and materials from deep sea ores
Bombara, G.
Maisano, S.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/905
en_US
With the long-term availability of the immense mineral resources represented by sea-bed nodules, the present deep crisis in the ferrous and non-ferrous metals industry offers a unique opportunity to critically review the resource-dispersive, speculative development system of the industrialized world, and establish a rational metals and materials policy.The polymetallic character of ocean nodules, which in the not-far-distant future could become a major source of metals to the entire world, appears to suggest the opportunity of turning from traditional carbothermic reduction of (monometallic) oxide ores to less energy consuming, more 'chemical' metallurgies, capable of extracting all the metal content from complex ores.In this viewpoint, the potential of carbochlorination for the processing treatment of nodules is assessed and some of the possible effects of ocean-ores exploitation on a new materials policy are considered.
oai:ojs.www.fracturae.com:article/906
2013-09-06T12:04:50Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/906
2013-09-06T12:04:50Z
Metallurgical Science and Tecnology
Vol. 3 No. 1 (1985)
The correlation between heat treatment, structure and mechanical characteristics in Inconel 718
Campo, E.
Turco, C.
Catena, V.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/906
en_US
The mechanical characteristics of Inconel 718 alloy resulting from the heat treatments currently used in industry are compared with those produced with a newly introduced treatment. The advantages obtainable with the latter concern the minimum creep rate and the characteristics of the welded joints. The results obtained are correlated with the particular physical metallurgy of the material under examination.
oai:ojs.www.fracturae.com:article/907
2013-09-06T12:15:00Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/907
2013-09-06T12:15:00Z
Metallurgical Science and Tecnology
Vol. 3 No. 2 (1985)
Cooperative phenomena and influence of strain energy in alloys
Cavallotti,, P.L.
Bergamaschi, R.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/907
en_US
Thermodynamic approximations for cooperative phenomena in solids are reviewed and a new approximation is proposed and developed. The method calculates the configurational free energy for Ising and Heisenberg model systems, from a series of quasi-chemical reactions, adopting a system renormalization solution strategy.Magnetic and suitable order-disorder transformations are properly represented as higher order transitions. An elastic energy term is introduced to take into account the atomic size and shape change effects in metallic alloys. With this method we can distinguish when an ordering transition becomes first order. The method is also suitable for a theoretical calculation of the magnetic free energy contribution to ferromagnetic alloys.
oai:ojs.www.fracturae.com:article/908
2013-09-06T12:15:00Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/908
2013-09-06T12:15:00Z
Metallurgical Science and Tecnology
Vol. 3 No. 2 (1985)
Production and service properties of micro-alloyed steel components for the motor industry
Baffigi, M.
Corso, S.
Giaccone, A.
Infante, l.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/908
en_US
In the mechanical engineering sector, there is now a marked trend towards the use of micro-alloyed steels in the form of long products as cost-effective substitutes for hardened and tempered steels. In addition to laboratory tests on the initial steels to check verifiable properties which can provide a first-step indication of properties in use, it is also important to ascertain the suitability of steels for various end applications by direct tests on components in actual service.The case of crankshafts considered in this paper represents the start of a comprehensive programme of tests on components initiated by Fiat Auto and can be regarded as one example of an approach to the problems of using micro-alloyed steels which was brought to a successful conclusion.
oai:ojs.www.fracturae.com:article/909
2013-09-06T12:15:00Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/909
2013-09-06T12:15:00Z
Metallurgical Science and Tecnology
Vol. 3 No. 2 (1985)
The Connecting Rod
Riccio, Giovanni
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/909
en_US
Like all components of the internal combustion engine, the connecting rod has been the object of significant changes in design and manufacturing, due to its function of primary importance.The article traces the evolution up to the present day of this metal component, examining the materials used and the latest innovations in manufacturing technologies.
oai:ojs.www.fracturae.com:article/910
2013-09-06T12:15:00Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/910
2013-09-06T12:15:00Z
Metallurgical Science and Tecnology
Vol. 3 No. 2 (1985)
The role of Cr, Al and Mn in the resistance of refractory steels to hot salt corrosion from combustion deposits
Bernabai, U.
Felli, F.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/910
en_US
Molten salts from combustion residues assume differentiated compositions depending on the type of fuel and the environmental variables The choice of resistant materials should be made on the basis of more specific criteria with respect to those adopted in hot air oxidation Three different kinds of steel (a) Fe-Cr-AI-Y, (b) Fe-Mn-Al, (c) Fe-Cr-Ni-Mn were tested in a basic mixture of molten salts (KCl-K2SO4-Fe2O3) occurring in the furnace of ferrous mineral agglomeration and in an acid one (Na2SO4-V2O5) typical of combustion systems using liquid hydrocarbons. This proved how chlorides are dangerous, particularly towards chromium-rich scales or matrices. Vanadium pentoxide is dangerous if it is associated with ferrous oxide. Manganese in the alloy helps with protection, particularly in sulphur-bearing atmospheres, also in the presence of chlorides, provided that there is no V2O5. Alloying with manganese is preferable in aluminium steels rather than in chromium steels, because of the high diffusivity of the element in Cr2O3 scales.
oai:ojs.www.fracturae.com:article/911
2013-09-06T12:15:08Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/911
2013-09-06T12:15:08Z
Metallurgical Science and Tecnology
Vol. 3 No. 3 (1985)
Aspects concerning the role of coatings in the production of iron castings by the "Policast" process
Delgaudio, G.
Sebramoglia, G.
Caironi, G.
Tosi, G.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/911
en_US
The "Policast" process is already in an advanced stage of industrialisation. However some interesting areas need further investigation in order to improve the effectiveness and consistency of the process.Among them there are the problems concerning the coatings used to cover the patterns of Expanded Polystyrene (EPS). In the present study, the porosity, the external appearance of the coating layers and the setting-up of the methodology and apparatus for permeability inspection are investigated. All these parameters are strictly interconnected, and they affect the success of the resultant castings, as demonstrated by systematic testing.
oai:ojs.www.fracturae.com:article/912
2013-09-06T12:15:08Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/912
2013-09-06T12:15:08Z
Metallurgical Science and Tecnology
Vol. 3 No. 3 (1985)
Influence of silicon on oxidation behaviour of Fe-Mn-Al and Fe-Mn alloys
Felli, F.
Bernabai, U.
Cavallini, M.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/912
en_US
A study was made of how the oxidation resistance in air of Fe-Mn-Al and Fe-Mn-C alloys at high temperatures is affected by the addition of small amounts, up to 3% silicon. An alloy containing 28% manganese, 8% aluminium, 2.4% silicon and 7 % carbon showed good behaviour up to 950°C, with a weight increase of less than 1 mgcm-2 after 170 hours of testing at constant temperature. As the silicon content fell there is an appreciable reduction in the limiting temperature for acceptable resistance. The alloys without aluminium already showed considerable oxidability at 600°C. Oxide formation mechanisms were examined as a function of time and temperature, with thermogravimetric tests and ESCA and EDS analyses.
oai:ojs.www.fracturae.com:article/913
2013-09-06T12:15:08Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/913
2013-09-06T12:15:08Z
Metallurgical Science and Tecnology
Vol. 3 No. 3 (1985)
Permanent magnets
Asti, G.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/913
en_US
An outline is given of the state of the art in permanent magnet technology with a brief discussion of the future perspectives opened up by the new materials. There is a growing demand for better performances associated with the expansion of applications and reduction in prices. The general principles that govern permanent magnet behaviour are discussed in some detail and a comparison of the variety of materials now available, with regard to both the intrinsic properties and technical characteristics, is presented.
oai:ojs.www.fracturae.com:article/915
2013-09-06T12:15:08Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/915
2013-09-06T12:15:08Z
Metallurgical Science and Tecnology
Vol. 3 No. 3 (1985)
Screws and bolts
Riccio, G.
2013-08-08
url:https://www.fracturae.com/index.php/MST/article/view/915
en_US
The development of these types of fasteners, which are traditional simple components has been very slow until recently, when the competition of other systems of joining has required better service properties and improved quality. As a consequence, great innovations in materials, design and production technology have been made.
oai:ojs.www.fracturae.com:article/916
2013-09-06T12:15:18Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/916
2013-09-06T12:15:18Z
Metallurgical Science and Tecnology
Vol. 4 No. 1 (1986)
Application of infra-red techniques to research on mechanical properties
Huang, Y.
Shih, C.H.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/916
en_US
Infra-red techniques can serve as a new tool, particularly useful in materials science research work. This paper describes the available techniques for infra-red temperature measurement and thermography, and provides experimental data for some metals and alloys, obtained by infra-red sensing during deformation and fatigue processes. It is shown that conventional tensile data can be correlated with the change in infra-red radiation which occurs during tensile stressing. The temperature field of a metal undergoing elastic-plastic deformation can be calculated using finite element analysis; on the other hand, the thermoelastic effect on the metal can be shown by thermography. Infra-red techniques can be used to predict fatigue damage, to monitor crack propagation and to give the alarm in the event of fracture. Finally, the irreversibility of the infra-red emission from the metal can be used as a basis for non-destructive testing.
oai:ojs.www.fracturae.com:article/917
2013-09-06T12:15:18Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/917
2013-09-06T12:15:18Z
Metallurgical Science and Tecnology
Vol. 4 No. 1 (1986)
Computer simulation of the solidification process in a three dimensional axisymmetric aluminium casting
Abis, S.
Fiorini, P.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/917
en_US
The Finite Element Method was used to determine the solidification pattern in a three dimensional axisymmetric aluminium casting. A modified temperature dependent specific heat Cp (T) function was considered to take into account the energy release at the solid-liquid interface. A static triangular mesh was used to simulate the physical domain. An experimental test was run to verify the accuracy of the numerical predictions on an actual Al 99,8% casting, by a careful monitoring of the temperature/time relationships at several points in the solidifying material. In particular, numerical results were compared with experimental ones, both in terms of macrostructure prediction and metallurgical behaviour, obtaining a fairly good agreement.
oai:ojs.www.fracturae.com:article/919
2013-09-06T12:15:18Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/919
2013-09-06T12:15:18Z
Metallurgical Science and Tecnology
Vol. 4 No. 1 (1986)
Mechanical and electrochemical alteration of sorbitic and austenitic steels charged with hydrogen
Biggiero, G.
Brevaglieri, B.
Picciuto, M.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/919
en_US
Experiments made with the method initiated by Hyspecka and Mazanek have revealed phenomena not encountered with other methods of investigation, such as the recovery of mechanical properties while still discharging, and the simultaneous effect on electrochemical voltage, which can only be due to a trasformation of the hydrogen state inside the metal. It was also observed experimentally that those processes are generalized, may be iterative, and occur for times correlated with the density of discharge.An attempt was also made, with very significant results, to correlate the variation in these mechanical properties, depending on the hydrogen charging time, with the much more easily achieved variation in electrochemical characteristics. Study of these phenomena was combined with examination of the fracture surfaces and numerous longitudinal diametral sections under the fractures, using a Cambridge 600 scanning electron microscope (SEM). The results for sorbitic steels were published as they became available (2-8) and an interpretative model was proposed based on them; the new results for austenitic steels, and for electrochemical tests, also seem capable of being referred to that model.
oai:ojs.www.fracturae.com:article/920
2013-09-06T12:15:18Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/920
2013-09-06T12:15:18Z
Metallurgical Science and Tecnology
Vol. 4 No. 1 (1986)
Superplasticity in a high-manganese (nickel free) stainless steel
Piatti, G.
Boerman, D.
Weir, H.A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/920
en_US
Mechanical (tensile tests) and microstructural (optical and scanning electron microscopy) investigations have been performed on a heavily cold-rolled nickel-free stainless steel plate having a nominal (weight percent) composition: 14 Cr-20 Mn-balance Fe. Preliminary results, showing superplastic behaviour exhibited by this high-manganese stainless steel, when deformed in the temperature range 20 to 900°C and at a low initial strain rateisi (£ 1.5x10-3 s-1), are reported and discussed.
oai:ojs.www.fracturae.com:article/921
2013-09-06T12:15:18Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/921
2013-09-06T12:15:18Z
Metallurgical Science and Tecnology
Vol. 4 No. 1 (1986)
The toughness of a cast hot-work tool steel
Roberti, R..
Balbi, M.
Giorgelli, C.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/921
en_US
The mechanical and technological properties of cast hot-work tool steels need to be fully exploited, since cast-to-form tools are increasingly utilized in many sectors of the forming industry. In the present research work, the fracture toughness of a cast H 11 hot-work tool steel is evaluated, using fracture mechanics and impact tests, on specimens machined from cast-to-form dies selected to represent different microstructural conditions. The results of the mechanical and toughness tests are compared with corresponding properties of wrought H 11 steel, and interpreted in terms of the microstructural characteristics of the cast steel.
oai:ojs.www.fracturae.com:article/922
2013-09-06T12:15:26Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/922
2013-09-06T12:15:26Z
Metallurgical Science and Tecnology
Vol. 4 No. 2 (1986)
Aluminium cylinder block
Riccio, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/922
en_US
Although aluminium has been used in the manufacture of cylinder blocks since the 1930s, the choice of this solution, and the problems involved in mass-production, are still studied and discussed. The most significant applications of aluminium in cylinder blocks and factors determining the choice of aluminium or cast iron are surveyed. Design of casting, technological aspects and choice of casting process are considered
oai:ojs.www.fracturae.com:article/923
2013-09-06T12:15:26Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/923
2013-09-06T12:15:26Z
Metallurgical Science and Tecnology
Vol. 4 No. 2 (1986)
Microfractographic characteristics and fracture toughness of 7000 and 2000 series aluminium alloys: proposal of a static fracture model
DI RUSSO, E.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/923
en_US
The results of SEM examinations performed on fracture surfaces of CT test pieces used for determining the toughness index KIC of five high strength aluminium alloys of 7000 and 2000 series, were correlated with the fracture toughness data obtained on such alloys. A relation was formulated, in a form suggested by fracture mechanics, which links the average width of the stretched zone of the five alloys with their KIC values. Moreover, a static fracture model was proposed, which reasonably explains the micromechanisms underlaying the formation of the cliff, that is the sharp discontinuity (step) joining the stretched zone to the overload fracture region.
oai:ojs.www.fracturae.com:article/924
2013-09-06T12:15:26Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/924
2013-09-06T12:15:26Z
Metallurgical Science and Tecnology
Vol. 4 No. 2 (1986)
New foundry process for the production of light metals in the semi-liquid, doughy state
Antona, P.L.
Moschini, R.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/924
en_US
Subjecting a metal alloy at the time of solidification to an elevated shear rate it is possible, upon solidification, to verify a microstructure very different from the conventional ones; the effect of the shear forces induced is, indeed, to destroy the solid network of dendritic interconnections developed during solidification of the liquid. In the absence of such a structure the dendrite fragments remain separate, and tend to assume spheroidal shapes by continual mutual mechanical collisions.The Fiat Research Centre has patented and developed a process that makes it possible to confer on the metallic alloy such globular structures based on the use of a capillary type static mixer.The present work describes the pilot plant able to produce semiliquid metal continuously, and illustrates the operating technique for producing a casting in the doughy state.Moreover, the microstructural characteristics of an Al-Si-Cu alloy cast in the semi-liquid state underline the inherent fluid-dynamic peculiarities possessed by such an alloy in the solidification range which allow it to be used easily in forming processes.
oai:ojs.www.fracturae.com:article/925
2013-09-06T12:15:26Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/925
2013-09-06T12:15:26Z
Metallurgical Science and Tecnology
Vol. 4 No. 2 (1986)
Recent innovations in the development of the "Policast" evaporative pattern process
Goria, C.A.
Magistrali, G.
Serramoglia, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/925
en_US
The Policast foundry process employs gasifiable expanded polystyrene patterns buried in loose sand and has already been introduced on the industrial scale. Research has therefore been concentrated on those of its features that are still open to further improvement, though satisfactory for the needs of high-volume manufacturing. Its aim is to reduce fabrication costs, improve product quality and make the process as a whole more reliable. Three of the innovations devised and perfected for this purpose are described. The first relates to a new procedure for making the metal tools used to mould the polystyrene foam patterns, based on electroforming, i. e. the electrodeposition of metals on suitably shaped supports that have been rendered conducting. The second innovation relates to a new system for the spheroidization of cast iron. This is carried out in special small ladles located outside the mould. Even so, it is similar in concept, and in terms of quality and yield, to in-mould spheroidization. In addition It is not specific to the Policast process, but can be adapted to any automatic pouring line It is particularly effective in overcoming certain constraints associated with Policast. The third innovation consists of the array of systems used for the instrumental checking of the most critical stage of the Policast process, namely compaction of the sand. These are systems and processes suitable for both on-line checking and experiments in the work-up of new castings.
oai:ojs.www.fracturae.com:article/926
2013-09-06T12:15:33Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/926
2013-09-06T12:15:33Z
Metallurgical Science and Tecnology
Vol. 4 No. 3 (1986)
Defect interpretation by Auger spectroscopy in problems arising in lubricating and degreasing steels
Biggiero, G.
Luzzi, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/926
en_US
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oai:ojs.www.fracturae.com:article/927
2013-09-06T12:15:33Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/927
2013-09-06T12:15:33Z
Metallurgical Science and Tecnology
Vol. 4 No. 3 (1986)
Influence of applied stress on the critical potential for stress corrosion of carbon steels in nitrate solutions
Alderisio, A.
Brevaglieri, B.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/927
en_US
-
oai:ojs.www.fracturae.com:article/928
2013-09-06T12:15:33Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/928
2013-09-06T12:15:33Z
Metallurgical Science and Tecnology
Vol. 4 No. 3 (1986)
Penetration kinetics of liquid sulphides in nickel and cobalt
Passerone, A.
Sangiorgi,, R.
Ricci, E.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/928
en_US
-
oai:ojs.www.fracturae.com:article/929
2013-09-06T12:15:41Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/929
2013-09-06T12:15:41Z
Metallurgical Science and Tecnology
Vol. 5 No. 1 (1987)
Electron channeling studies of local surface deformation in HSLA steel
Kaczorowski, M.
Gerberich, William W.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/929
en_US
The deformation process in high strength low-alloy (HSLA) steel has been investigated using transmission and scanning electron microscopy. Electron channeling contrast and selected area channeling pattern (SACP) techniques reveal microscopic orientation changes developing during deformation by tension. Theoretical modeling involves an accounting procedure based on dislocations emanated at grain boundary sources. This has shown that a length scale (subcell diameter) might be utilized to predict strain-hardening behavior with a dislocation source length coefficient of ~ 2.2 and Taylor work hardening coefficient, a = 0.44.
oai:ojs.www.fracturae.com:article/930
2013-09-06T12:15:41Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/930
2013-09-06T12:15:41Z
Metallurgical Science and Tecnology
Vol. 5 No. 1 (1987)
Preferred orientation in drawn austenitic stainless steel
Roberti, R.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/930
en_US
This paper describes the development of crystallographic preferred orientations in a type AISI304L austenitic stainless steel as a function of increasing reductions in area achieved by drawing at room temperature.In order to investigate these crystallographic textures X-ray diffraction measurements were made on transverse and longitudinal sections of the drawn rods and results are expressed in terms of texture coefficients and inverse pole figures.The results have shown that the initial duplex <111 > + <100> fibre texture of the rolled and solution annealed starting rod develops towards a single <111 > fibre preferred orientation along the fibre axis with increasing true drawing strain.The single <111 > fibre texture is consistent with the preferred orientations observed in low stacking fault energy face centered cubic polycrystalline metals and alloys and with the lack of dynamic recrystallization due to the low homologous temperature of deformation. Martensitic a phase was detected in the cold worked rods since the early stages of plastic deformation and was found to be strongly textured with a single <110> fibre preferred orientation, typical of polycrystalline body centered cubic metals and alloys.
oai:ojs.www.fracturae.com:article/931
2013-09-06T12:15:41Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/931
2013-09-06T12:15:41Z
Metallurgical Science and Tecnology
Vol. 5 No. 1 (1987)
Solidification of infiltrated metal matrix composites
Flemings, M.C.
Mortensen, A.
Cornie, J. A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/931
en_US
This paper describes one portion of a broad continuing program at Massachusetts Institute of Technology on metal matrix composites. It deals with solidification of fibrous composites during and after infiltration The fibers influence solidification in important ways by restricting the maximum size to which a dendrite arm can grow by "ripening". More remarkably, the dendritic structure in composites is completely eliminated at longer solidification times, as a result of "coalescence " and of enhanced solid diffusion. The result is that substantially more homogeneous structures can be obtained in metal-matrix composites than in usual castings and ingots.
oai:ojs.www.fracturae.com:article/932
2013-09-06T12:15:41Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/932
2013-09-06T12:15:41Z
Metallurgical Science and Tecnology
Vol. 5 No. 1 (1987)
The Piston
Riccio, Giovanni
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/932
en_US
The piston, due to its functions of primary importance, is one of the most refined components of the internal combustion engine.This article, following the evolution of the piston up to the present day, focuses principally on the new materials currently used and innovations in processing techniques.
oai:ojs.www.fracturae.com:article/933
2013-09-06T12:15:49Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/933
2013-09-06T12:15:49Z
Metallurgical Science and Tecnology
Vol. 5 No. 2 (1987)
High-temperature oxidation behaviour of Fe-Mn-AI-Si-C alloys in thermal cycling tests
Cavallini, M.
Felli, F.
mazzoni, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/933
en_US
A study was made of the behaviour under thermal cycling in air of a series of Fe-Mn-AI-Si-C alloys which had shown good resistance to isothermal oxidation tests. Alumina based oxides are formed interspersed with spinels more or less rich in manganese. These spinels undergo microspalling during the cycling, with a continuous loss of materials contained, within acceptable values up to a temperature of 750°C. The role of silicon is particularly important in supporting the formation of the alumina film and in promoting the diffusion of manganese instead of iron in the formation of the spinels, which result in higher resistance to thermal shocks.
oai:ojs.www.fracturae.com:article/934
2013-09-06T12:15:49Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/934
2013-09-06T12:15:49Z
Metallurgical Science and Tecnology
Vol. 5 No. 2 (1987)
Hot strength, dynamic recovery and dynamic recrystallization of 317 type stainless steel
Evangelista, E.
McQueeim, H.J.
Ryan, N.D.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/934
en_US
Hot torsion tests were performed to fracture on type 317 stainless steel in both the as-cast and the worked condition, at temperatures between 900 and 1200°C and strain rates of 0.1-5 s-1 in order to study the microstructure responsible for hot workability behaviour. Each flow curve exhibited a peak followed by a decrease to a steady-state regime as a result of dynamic recovery and dynamic recrystallization. The hypothetical saturation stress due to dynamic recovery and the critical stress for dynamic recrystallization were determined from the strain hardening rate vs stress plots. The dependence of flow stress on temperature followed an Arrhenius function with an activation energy of 508 kJ/mol for the as-cast and 496 kJ/mol for the worked material. The role of 5 ferrite particles on dynamic restoration and on mechanical behaviour was analyzed. The subgrain and recrystallized grain sizes were related to the conditions of deformation.
oai:ojs.www.fracturae.com:article/935
2013-09-06T12:15:49Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/935
2013-09-06T12:15:49Z
Metallurgical Science and Tecnology
Vol. 5 No. 2 (1987)
Laser surface remelting and alloying of aluminium alloys
Moschini, R.
Appiano, S.
Antona, P.L.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/935
en_US
Aluminium alloys offer notable advantages in the manufacture of structural components, but generally they have poor tribological behaviour characteristics.Such disadvantages can be lessened by adequate surface treatments, which do not compromise the over-all properties of the material used Laser surface remelting and alloying treatments enable the obtainment of surface layers of an adequate thickness, characterized by distinct metallurgical properties.By laser surface alloying it is possible to alter the metallurgical and mechanical characteristics of the sublayer submitted to radiation by addition on its surface of a predetermined quantity of chemical elements melted together with the base material.By suitable techniques, it is possible to achieve sound alloyed layers of no less than one millimetre thick, with hardness values of over 200 HV, obtained with laser powers that are industrially acceptable in decidedly short treatment times.By simply remelting it is possible to drastically reduce or even eliminate pre-existing porosity in the material submitted to laser radiation by exploiting the rapid solidification of thin surface layers, and consequently remarkable benefits in terms of tensile strength and ductility are achieved and hence, also thermical fatigue resistance.
oai:ojs.www.fracturae.com:article/936
2013-09-06T12:15:49Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/936
2013-09-06T12:15:49Z
Metallurgical Science and Tecnology
Vol. 5 No. 2 (1987)
Wheels
Riccio, Giovanni
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/936
en_US
In the early days of this century, automobile pioneers were still arguing about whether wooden or metal wheels gave the better performance. But soon, in 1924, the first wheel in light alloy, mounted on a Bugatti, made its appearance on the occasion of the French Grand Prix. The article, following the evolution of wheels for cars and heavy vehicles, focuses on their characteristics and the innovations brought in, affecting both the materials used and the manufacturing process.
oai:ojs.www.fracturae.com:article/938
2013-09-06T12:15:58Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/938
2013-09-06T12:15:58Z
Metallurgical Science and Tecnology
Vol. 5 No. 3 (1987)
Abrasive wear resistance of austempered ductile iron at room temperature
Schissler, J.M.
Brenot, P.
Chobaut, J.P.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/938
en_US
The use of austempered ductile iron obtained by heat treating spheroidal-graphite cast iron is very important in the gear industry. However the nature of the bainitic structure, which is used to improve wear resistance, has never been fully identified. The aims of this study were:- to optimize the upper bainitic structures in S. G. cast irons (usually called austempered ductile iron or A. D. I.) to have the best abrasive wear resistance at room temperature.- to study the influence of the solidification cell characteristics upon these optimized structures.- to determine the evolution of the microstructures during the abrasion test.Results clearly indicate the primordial influence of the retained austenitic phase. A high percentage of retained austenite promotes a high abrasive wear resistance. The analysis of the results shows that this austenitic phase is heterogeneous. The best abrasive wear resistance is associated with the lowest hardness value. During abrasion, austenite at or near the surface is gradually and partly transformed to martensite.
oai:ojs.www.fracturae.com:article/939
2013-09-06T12:15:58Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/939
2013-09-06T12:15:58Z
Metallurgical Science and Tecnology
Vol. 5 No. 3 (1987)
Design optimisation problems of stress corrosion in welded joints in 7000 alloy
Abis, S.
Di Russo, E.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/939
en_US
The use of thick plates of high-strength aluminium alloys, in specific welded structures, gives the designer many optimisation problems concerning the prediction and elimination of brittle fracture in the welded joints, caused by stress corrosion in the zone next to the weld beads. The Istituto Sperimentale dei Metalli Leggeri has faced and worked out these problems, in parallel with investigations of a metallurgical nature concerning the microstructural characteristics of the base metal in the heat affected zone (HAZ) next to the weld.The results of these studies enabled us to define, with the aid of appropriate structural calculation techniques, some design schemes which ensure a high resistance to brittle fracture by stress corrosion in special welded joints. This paper investigates and discusses such problems.
oai:ojs.www.fracturae.com:article/940
2013-09-06T12:15:58Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/940
2013-09-06T12:15:58Z
Metallurgical Science and Tecnology
Vol. 5 No. 3 (1987)
Materials for the fusion reactor
Matera, R.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/940
en_US
Development of fusion technology Is a long-term objective of the European Community, covering the construction at ten-year intervals of an experimental reactor, a demonstration reactor, and lastly the commercial reactor, based on magnetic confinement of a plasma of deuterium and tritium. Problems relating to materials involved in the programme are analysed with special reference to the reactor structures most directly exposed to the actions of the plasma and neutron flux. For the experimental reactor, in which the most complex problem concerns the interactions of such structures with the plasma, the possible solutions are necessarily limited to a few steels currently used in nuclear engineering For subsequent reactors the emphasis is on resistance to neutron damage and reduction of induced radioactivity. In that context steels and vanadium alloys with a highly controlled composition in regard to the presence of a number of elements are being studied. Development of such materials could allow exploitation of this inexhaustible energy source with extremely low environmental costs.
oai:ojs.www.fracturae.com:article/941
2013-09-06T12:15:58Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/941
2013-09-06T12:15:58Z
Metallurgical Science and Tecnology
Vol. 5 No. 3 (1987)
Springs
Riccio, Giovanni
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/941
en_US
The advent of the automobile provided many important new uses for springs. In this paper various types of springs used for the suspensions, the shock absorbers, engine valves and the clutch are presented and discussed. The most significant changes in design and manufacturing process are also considered.
oai:ojs.www.fracturae.com:article/942
2013-09-06T12:16:10Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/942
2013-09-06T12:16:10Z
Metallurgical Science and Tecnology
Vol. 6 No. 1 (1988)
A computer program for the calculation of stresses and strains in the axisymmetric cup drawing
Orlando, M.
Pagannone, M.
Perotti, G.
Podda, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/942
en_US
The proposed computer program is developed incorporating previous results by WOO, as well as taking into account the cup wall, whose exact solution had not been previously sought. The calculations are performed in this case starting both from the punch side as well as from the die side, so as to individuate the position of the section of the cup wall on both sides of which the computed values of stresses and strains are the same within defined limits. The results are in this way generalized to cup walls that form contact angles different from 90° with the initial blank position.
oai:ojs.www.fracturae.com:article/943
2013-09-06T12:16:10Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/943
2013-09-06T12:16:10Z
Metallurgical Science and Tecnology
Vol. 6 No. 1 (1988)
Manganese diffusion coating of cast irons
Boghetich, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/943
en_US
Previous work on the diffusion coating on steels and cast iron has been followed by systematic experiments on five types of cast irons with flake or nodular graphite.Considerable diffusion depths were obtained at treatment temperatures somewhat lower than those previously used for steels. The treatment resulted in a very hard surface diffusion; primarily composed of manganese-replaced cementite.
oai:ojs.www.fracturae.com:article/944
2013-09-06T12:16:10Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/944
2013-09-06T12:16:10Z
Metallurgical Science and Tecnology
Vol. 6 No. 1 (1988)
Morphology of localised attacks on 304 austenitic stainless steel stressed by constant tensile load
Alderisio, A.
Bianchi, M.
Brevaglieri, B.
Signorelli, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/944
en_US
Differents forms of localised etch appear on solution heat-treated austenitic stainless steel exposed to solutions of H2SO4 + NaCl according to the SO4/Cl ratio, under well-defined experimental conditions: presence of pre-formed cavities, application of constant load, polarization to a potential in the region of imperfect passivity.The forms of etch and the effect of the various parameters are discussed.
oai:ojs.www.fracturae.com:article/945
2013-09-06T12:16:10Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/945
2013-09-06T12:16:10Z
Metallurgical Science and Tecnology
Vol. 6 No. 1 (1988)
Neutron small angle scattering on Udimet 720 Ni superalloy turbine blade. Non destructive analysis of the g’ precipitation
Bianchi, P.
D'Angelo, D.
Carsughi, F.
Rustichelli, F.
Magnani, M.
Stefanon, M.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/945
en_US
An investigation on thermal treatment effects on Udimet 720 Ni superalloy was performed by using neutron small angle scattering. In particular y' precipitation was considered. The sample was obtained from a turbine blade used in a generator of electricity power. The measurement was performedattheDIl in the InstituteLaue Langevinin Grenoble. The neutron wavelength wasX = 1 nm. Themicrostructuraldata were compared with those obtained by transmission electron microscopy. A satisfactory agreement appeared in the size distributions obtained by using the two techniques. The feasibility of non destructive microstructural tests was so demonstrated
oai:ojs.www.fracturae.com:article/946
2013-09-06T12:16:10Z
MST:ART
v2
https://www.fracturae.com/index.php/MST/article/view/946
2013-09-06T12:16:10Z
Metallurgical Science and Tecnology
Vol. 6 No. 1 (1988)
The technical and economic advantages of lightweight aluminium alloy wheels
Caglioti, G.
Doniselo, -
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/946
en_US
Lightweight aluminium alloy rolled wheels are compared with aluminium alloy cast wheels. Rolled wheels offer advantages of technical and economic nature that make them worthy of consideration with a view to their use also for mass production cars.
oai:ojs.www.fracturae.com:article/947
2013-09-06T12:16:18Z
MST:ART
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2013-09-06T12:16:18Z
Metallurgical Science and Tecnology
Vol. 6 No. 2 (1988)
Experimental evaluation of the thermal characteristics of internal combustion engine cylinder liners
Doniselli, C.
Gorla, C.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/947
en_US
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oai:ojs.www.fracturae.com:article/948
2013-09-06T12:16:18Z
MST:ART
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2013-09-06T12:16:18Z
Metallurgical Science and Tecnology
Vol. 6 No. 2 (1988)
Influence of residual stesses on fatigue crack propagation
Sirtori, S.
Vergani, L.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/948
en_US
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oai:ojs.www.fracturae.com:article/949
2013-09-06T12:16:18Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/949
2013-09-06T12:16:18Z
Metallurgical Science and Tecnology
Vol. 6 No. 2 (1988)
Ion-nitriding of austenitic stainless steels
Angelini, E.
Burdese, A.
De Benedetti, B.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/949
en_US
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oai:ojs.www.fracturae.com:article/950
2013-09-06T12:16:18Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/950
2013-09-06T12:16:18Z
Metallurgical Science and Tecnology
Vol. 6 No. 2 (1988)
Riserless casting of spheroidal graphite cast ironin rigid moulds
Mampaey, F.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/950
en_US
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oai:ojs.www.fracturae.com:article/951
2013-09-06T12:16:26Z
MST:ART
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https://www.fracturae.com/index.php/MST/article/view/951
2013-09-06T12:16:26Z
Metallurgical Science and Tecnology
Vol. 7 No. 1 (1989)
Manufacture and bench qualification of a road vehicle steering knuckle produced by pressing an aluminium alloy in the semiliquid state
Bernard, L.
Moschimi, R.
Ronchiato, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/951
en_US
Road vehicle steering knuckles in aluminium alloy AS7U3G rheocast in the semiliquid state were pressed and subjected to a series of tests to determine the mechanical and metallurgical characteristics of this material. Bench qualification tests were then run in the form of fatigue tests simulating the most severe condition envisaged in the design stage. The results showed that the design dimensions were satisfactory in relation to the observed strength of the components.
oai:ojs.www.fracturae.com:article/952
2013-09-06T12:16:26Z
MST:ART
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2013-09-06T12:16:26Z
Metallurgical Science and Tecnology
Vol. 7 No. 1 (1989)
Microstructural transitions and growth features in rapid solidification: a comparison between experimental fact and quantitative prediction
Jones, H.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/952
en_US
Microstructural transition has been recognised as a ubiquitous feature of rapid solidification more or less from the outset but progress in the interpretation of such behaviour has been limited until relatively recently. The present contribution reviews this recent progress in understanding based on comparison of quantitative predictions with experimental observations made under conditions of rapid solidification that were well- controlled and well-characterized. It is concluded that, while the extent of agreement between prediction and observation is encouraging so far, further progress will depend on the continued acquisition of definitive experimental information to provide critical tests of theory where no useful measurements presently exist.
oai:ojs.www.fracturae.com:article/953
2013-09-06T12:16:26Z
MST:ART
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2013-09-06T12:16:26Z
Metallurgical Science and Tecnology
Vol. 7 No. 1 (1989)
Preformed pits as initiation sites for stress corrosion of austenitic stainless steels
Alderisio, A.
Brevaglieri, B.
Signorelli, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/953
en_US
A study has been made of the effect of preformed pits on the corrosion behaviour of a heat-treated AISI304 austenitic stainless steel under constant load equal to 80% sp(0.2), at polarization potentials in the imperfect passivity region and under open circuit conditions, exposed to aqueous solutions with diverse SO4/Cl ratios.With polarization in the passive range and a ratio of 1/0.2, as in the first stage of stress corrosion, intergranular attack on the bottom of pits with critical dimensions has been observed. On the walls of the cracks there are characteristic signs of transgranular attack. An increase in temperature causes an increase in the rate of the phenomenon, without leading to the appearance of different forms of corrosion. With polarization in the active range the trend of the crack is always transgranular. Sometimes the crack walls appear to be marked with fine parallel pleats, parallel grooves and micropits. In some conditions - low temperature and very small pits - the formation of martensite, attacked in a highly selective manner, prevents stress corrosion.
oai:ojs.www.fracturae.com:article/954
2013-09-06T12:16:35Z
MST:ART
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2013-09-06T12:16:35Z
Metallurgical Science and Tecnology
Vol. 7 No. 2 (1989)
Coachwork
Riccio, Giovanni
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/954
en_US
The coachwork is the last step of manufacturing of motor-cars. It is the part more exposed to the judgement of the public and for this reason very important in commercial sense.This article explains the chief points of evolution of technique and taste on this subject.
oai:ojs.www.fracturae.com:article/955
2013-09-06T12:16:35Z
MST:ART
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2013-09-06T12:16:35Z
Metallurgical Science and Tecnology
Vol. 7 No. 2 (1989)
Evoluation of bond efficiency of aluminium- polyethylene adhesive joint
Biggiero, G.
Insam, A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/955
en_US
The main purpose of this article concerns the application of ultrasonic methods to predict the limits of adhesive joint efficiency. Ultrasonic data are related to metal-polymer adhesion phenomena by studying joints strength, fracture morphoiogy and surface chemistry (ESCA).Cohesive or adhesive joint failures are predictabie by non-destructive inspection of metal-adhesive interface.
oai:ojs.www.fracturae.com:article/956
2013-09-06T12:16:35Z
MST:ART
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2013-09-06T12:16:35Z
Metallurgical Science and Tecnology
Vol. 7 No. 2 (1989)
Laser welding and subcriticai annealing of a 2Cr-1Mo steel for pipes operating at high temperatures
Cerri, W..
Mor, G.P.
Balbi, M.
Zavanella, T.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/956
en_US
Experiments were performed to perfect a process for the CO 2 laser welding of an ASTMA335 grade P22 steel for pipes operating at high temperatures. The corresponding conventional welding techniques require a rather complicated schedule that includes both pre- and post- heating to prevent cracks and martensite formations in melted and heat affected areas, and has a mean duration of several hours. Qualification of the laser-welded joints was performed according to section IX of the ASME standards. The following results were obtained:- defect-free joints without any form of preheating;- a post-weld subcriticai annealing process able to reduce the hardness of the melted area to 280 HVin a few minutes (the hardness of the as- welded melted zone is around 400 HV); a similar process was applied at the end of the weld pass by modulating the power density delivered to the welded joint.Correct temperature distribution during annealing was ensured by means of a control system using a two-colour optical pyrometer focussed on the joint surface, and computerised checking of the incident laser power.
oai:ojs.www.fracturae.com:article/957
2013-09-06T12:16:35Z
MST:ART
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2013-09-06T12:16:35Z
Metallurgical Science and Tecnology
Vol. 7 No. 2 (1989)
Microalloyed steel applications in high-rate hot forging processes
A. Blarasin, A.
Farsetti, P.
Marengo, M.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/957
en_US
Worthwhile process savings are obtained in the hot-forging of components by using automated high-rate plants and microalloyed steels that do not require subsequent quenching and tempering. This paper describes and discusses the mechanical and fatigue properties of a series of microalloyed steels. Present and foreseen applications are also reviewed with regard to the automotive industry.Lastly, some suggestions are made concerning the correct choice of materials and components to ensure reliability in the application of this class of steels.
oai:ojs.www.fracturae.com:article/958
2013-09-06T12:16:42Z
MST:ART
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2013-09-06T12:16:42Z
Metallurgical Science and Tecnology
Vol. 8 No. 1 (1990)
Determination of thermal diffusivity for the correct design of iron castings
Borchiellini, Romano
Cali, Michele
De Benedetti, Bruno
Giaretto, Valter
Goria, Carlo Alberto
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/958
en_US
A fuller understanding of the thermophysical characteristics of cast iron has been rendered necessary by recent changes in the design and manufacture of mechanical components, especially those employed in the automotive industry.Thermal diffusivity is of particular importance in this respect. Its determination by means of a transient thermal step method is described in this paper. A thermal step is induced in test specimens by their rapid transfer from one thermostated environment to another at a higher temperature. Temperatures are then taken during the transient step at a point with known coordinates.Simulation of this transient under different heat exchange conditions with a finite elements model (FEM), which can handle specimens of varying geometry, gives a grid formed of points representing Biot and Fourier numbers, and temperature values 9 standardised within the range zero to one.Thermal diffusivity is determined by taking the Biot and Fourier numbers that minimise the difference between the values observed experimentally and those on the curve supplied by the model. This parameter is then correlated with the metallurgical characteristics.
oai:ojs.www.fracturae.com:article/959
2013-09-06T12:16:42Z
MST:ART
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2013-09-06T12:16:42Z
Metallurgical Science and Tecnology
Vol. 8 No. 1 (1990)
Nucleation of fatigue cracks at the notch tip
Vergani, Laura
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/959
en_US
Notch tip fatigue and fracture behaviour is influenced by local plastic yielding, the extent of which is determined by the notch itself. In this paper, an assessment is made of the influence of the stress-strain gradient on nucleation of notch tip fatigue cracks. The results of a series of experiments performed with a range of theoretical notch factor K, values are compared with those calculated by applying the Coffin- Manson relation and Neuber's formula.
oai:ojs.www.fracturae.com:article/960
2013-09-06T12:16:42Z
MST:ART
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2013-09-06T12:16:42Z
Metallurgical Science and Tecnology
Vol. 8 No. 1 (1990)
Stimulation of various forms of stress corrosion in an austenitic stainless steel
Alderisio, Antonio
Brevaglieri, Bruno
Natali, Stefano
Signorelli, Giuseppe
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/960
en_US
A heat-treated AISI304 austenitic stainless steel has been studied in a 1N H2SO4 + 0.2N NaCl solution at constant load and at room temperature and80°C.The SEM examination has been used to ascertain the morphology and evolution of attack, initiated at preformed pits having critical dimensions, owing to the effect of polarization in the imperfect passivity zone and subsequently, alternatively in the regions of perfect passivity, active-passive transition, activity and in freely-corroding conditions. Reverse and direct polarization sequences have been investigated.It has been observed that in some cases the integranular mode of attack changes to transgranular. In other cases it is intensified. While in yet others it is depressed. Attack that is initially transgranular cannot be modified to intergranular.With the methodologies applied it has been possible at will to induce the appearance of various stress-corrosion cracking forms or to ensure the degeneration thereof into other forms of attack.
oai:ojs.www.fracturae.com:article/961
2013-09-06T12:17:14Z
MST:ART
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2013-09-06T12:17:14Z
Metallurgical Science and Tecnology
Vol. 8 No. 2 (1990)
A Wrought Iron Railing of the 16th Century
Violi, G.
Verdini, B.
Gauzzi, F.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/961
en_US
Specimens from a wrought iron railing placed on the Marcus Aurelius Column during the 16th century have been examined with metallographic methods. They show a very heterogeneous structure with many oxide and silicate inclusions and frequent mechanical twins in the ferrite grains. The inclusions have been studied with microanalysis EDS apparatus. The results of the study of the bloomery iron are discussed also in comparison with the iron-making techniques as described by Biringuccio in order to infer additional informations on the manifacturing methods that were used.
oai:ojs.www.fracturae.com:article/962
2013-09-06T12:17:14Z
MST:ART
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2013-09-06T12:17:14Z
Metallurgical Science and Tecnology
Vol. 8 No. 2 (1990)
Influence of Ghost Lines on the Performance of Continuously Cast Special Structural Steels
Fattorini, F.
Baffigi, M.
Digianfrancesco, D.
Rigoni, S.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/962
en_US
An assessment was made of the in-use performance of special structural steels produced by the ingot and the continuous casting (c.c.) process. Particular attention has been paied to the influence of the ghost lines occasionally observed in c. c. products on the behaviour of mechanical components. Steel 40CrMo4 used by Fiat Auto for the manufacture of car front wheel hubs was studied in terms of its strength, ductility, low and high cycle fatigue resistence. Rotating bending fatigue tests were also performed on wheel hubs under simulated on-road conditions. A complete correspondence was observed between the metallurgical, static and dynamic properties of the steel produced by the two fabrication processes.
oai:ojs.www.fracturae.com:article/963
2013-09-06T12:17:14Z
MST:ART
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2013-09-06T12:17:14Z
Metallurgical Science and Tecnology
Vol. 8 No. 2 (1990)
The Sand Coated Die
Mampaey, F.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/963
en_US
The sand coated die is composed of a casting and a die which are separated by a layer of variable sand thickness. Increasing sand thickness will reduce the chilling influence of the die and hence augment the solidification time of the casting. A computer model has been developed which accurately predicts the relative solidification time in the sand coated die. This model, validated for several cast metals, is in close agreement with the experimental data of the present research as well as with the ones published previously in literature. At the interface sand-die no perfect conduction contact exists. This may be explained by a simplified model of sand grains packing.
oai:ojs.www.fracturae.com:article/964
2013-09-06T12:17:23Z
MST:ART
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2013-09-06T12:17:23Z
Metallurgical Science and Tecnology
Vol. 8 No. 3 (1991)
Tests and Examinations of theOldHône-BardRailwayBridge
Nicodemi, W.
Boniardi, M.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/964
en_US
Mechanical and metallographic tests were run on surviving fragments of the late-19th-century Hone-Bard railway bridge demolished in the Sixties to assess the characteristics of the “agglomerated” (similar to «wrought») iron used in their construction. An explanation is also offered of the surprising discrepancy between the lab data for this iron and its brilliant service record.
oai:ojs.www.fracturae.com:article/965
2013-09-06T12:17:31Z
MST:ART
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2013-09-06T12:17:31Z
Metallurgical Science and Tecnology
Vol. 9 No. 1 (1991)
Commercial Al Li alloy plates have a tendency to form intergranular delamination cracks extending in the rolling direction during fracture.
Cavallini, M.
Felli, F.
Delogu, P.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/965
en_US
The poor grain boundary strength induces low toughness failures when the principal stress acts through the thickness. On the other hand, a delamination toughening mechanism occurs when the stress is applied in longitudinal and transverse directions. During fatigue crack growth at low R load ratios a strong closure effect occurs. AES analyses on freshly broken surfaces reveal that intergranular fracture occurs also with absence from the grain boundaries not only of Li, but also of K or Na impurities.
oai:ojs.www.fracturae.com:article/966
2013-09-06T12:17:31Z
MST:ART
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2013-09-06T12:17:31Z
Metallurgical Science and Tecnology
Vol. 9 No. 1 (1991)
Diffusion Processes of Aluminium Coatings for the Protection of Austenitic Stainless Steels
Alderisio, A.
Brevaglieri, B.
Natali, S.
Dang, A.
Capuano, G.A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/966
en_US
An aluminium-coated austenitic stainless steel has been subjected to heat treatments of various durations. The process has led to the formation of inter diffusion zones with characteristic non-directional and columnar structures.The formation of in termetallic compounds such as NiAl or Ni3Al prevails in the non-directional type, while substitutional solid solutions occur in the "columnar " type.One or both these structures can be obtained by balancing and regulating process activity through adequate heat treatments.The development of one or both structures can heighten the characteristics of the coating as regards coating protection or oxidation resistance at high temperatures.
oai:ojs.www.fracturae.com:article/967
2013-09-06T12:17:31Z
MST:ART
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2013-09-06T12:17:31Z
Metallurgical Science and Tecnology
Vol. 9 No. 1 (1991)
Sensitivity Analysis of Deep Drawing Process Control Parameters
Caviasso, G.
Fontana, R.
Marinsek, G.
Guida, M.
Porraro, G.
Strona, P.P.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/967
en_US
The problem of sheet metal stamping in general was analyzed, defining the parameters involved and the objectives to be reached for process optimization.D.O.E. (Design of experiments) and statistical analysis (ANOM, ANOVA) techniques were applied to the case of a component which, though of geometrically simple configuration, was representative of the process.The objective of the work was methodological: through this application, it was possible to develop a series of procedures and obtain positive initial results, particularly as regards sensitivity analysis for the parameters involved.
oai:ojs.www.fracturae.com:article/968
2013-09-06T12:17:31Z
MST:ART
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2013-09-06T12:17:31Z
Metallurgical Science and Tecnology
Vol. 9 No. 1 (1991)
Structural Effects of Tempering on Cr Steels for Reactors
Brunelli, L.
Gondi, P.
Montanari, R.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/968
en_US
Structural evolution during tempering at various temperatures of martensitic steels has been followed by means of X-ray diffraction analysis metallography in SEM and hardness measurements.Effects of Cr content and of quenching rate have been considered. Persistence of large internal strains has been found even after full recovery of hardness. These strains are related with the large densities of bubble and void nucleation centres, which seem responsible for the swelling resistance of these alloys.
oai:ojs.www.fracturae.com:article/969
2013-09-06T12:17:38Z
MST:ART
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2013-09-06T12:17:38Z
Metallurgical Science and Tecnology
Vol. 9 No. 2 (1991)
Experimental Measurement of the Temperature Rise Generated During Dynamic Crack Growth in Metals
Rosakis, A J.
Zehnder, A.T.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/969
en_US
During the high speed propagation of cracks, large temperature increases occur at the crack tip due to the intense dissipation of plastic work there. This increased temperature may have a significant effect on the material's dynamic fracture toughness. An experimental investigation of the temperature fields at the tip of dynamically propagating cracks in 4340 steel was performed using a focused array of high speed infrared detectors. Temperature fields were measured for cracks growing at speeds from 700 m/s to 1900 m/s. Maximum temperature increases were as high as 465°C. The temperature fields were differentiated to determine the plastic work rate distribution at the crack tip and to estimate the plastic strain rate. Effects of crack tip heating on dynamic fracture toughness are discussed.
oai:ojs.www.fracturae.com:article/970
2013-09-06T12:17:38Z
MST:ART
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2013-09-06T12:17:38Z
Metallurgical Science and Tecnology
Vol. 9 No. 2 (1991)
Non Equilibrium Phase Transitions in Intermetallics
Martin, G.
Bellon, P.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/970
en_US
Intermetallics are operating under conditions where theatomic order is permanently disturbed from it's thermodynamical optimum, phase equilibria may no more be predicted from the classical free energy functions. Nevertheless, under simplifying assumptions, one may construct a new function, playing a similar role for assessing the respective stability of various phases: the latter is based on microscopic data such as atomic jump frequencies and interatomic binding energies, but does not imply an internal energy! After giving some examples of practical relevance of the present theory, we present the guiding ideas on which it relies, show it's present limitations and some examples where it is applied, at least as a qualitative guide, for rationalizing e.g. complex processing techniques such as mechanical alloying or subtile irradiation effects on the stability of intermetallics.
oai:ojs.www.fracturae.com:article/971
2013-09-06T12:17:38Z
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2013-09-06T12:17:38Z
Metallurgical Science and Tecnology
Vol. 9 No. 2 (1991)
Notch Effect on Fatigue Behaviour of Microalloyed Forging Steels
Balbi, M.
Boniardi, M.
Giglio, M.
Vergani, L.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/971
en_US
The fatigue behaviour of a microalloyed forging steel was analysed at two hot-forging temperature levels - one at1240°Ccorresponding to the ordinary heating parameters and the other at1060°Csuited to obtain a finer grain size. The resulting behaviour was then compared with a conventional hardened and tempered steel. Fatigue tests were carried out both on smooth and keyhole-type notched specimens. The fatigue test nucleation was studied on smooth test pieces, and the resulting experimental data were then used to predict the fatigue life of notched specimens.Contrarily to what happens with hardening and tempering steels, predictions for microalloyed steels are almost never conservative.
oai:ojs.www.fracturae.com:article/972
2013-09-06T12:17:38Z
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2013-09-06T12:17:38Z
Metallurgical Science and Tecnology
Vol. 9 No. 2 (1991)
Plastic Anisotropy in Aluminium - Effect of Texture and Microstructure
Juul Jensen, D.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/972
en_US
The effects of crystallographic texture and deformation microstructure on the flow stress anisotropy in aluminium are reviewed. The texture is measured by neutron diffraction and the textural contribution to the anisotropy is determined by model calculations. It was found that texture can have very large effects on the anisotropy. However, for most experimental conditions, texture effects alone cannot explain the observed anisotropy. In those cases the non texture part of the anisotropy is caused by microstructural effects, and the relation between development of macroscopically oriented microbands and the "microstructural anisotropy " is discussed. Finally the effects of various materials and processing parameters on the flow stress anisotropy, the texture, the microstructure and on the relative importance of texture microstructure effects on the anisotropy is discussed.
oai:ojs.www.fracturae.com:article/974
2013-09-06T12:17:38Z
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2013-09-06T12:17:38Z
Metallurgical Science and Tecnology
Vol. 9 No. 2 (1991)
The Utility of Torsion in Hot Workability Testing of Metallic Materials
Evangelista, E
McQueen, H.J.
Ryan, N.D.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/974
en_US
The hot torsion test has proven very versatile in determining high temperature (> 0.5 Tm) characteristics at constant strain rates of l0-3 to 102 s-1.The stress-strain and strain hardening curves are suitable bases for constitutive equations giving temperature and strain rate dependencies. Critical points in the above curves in association with metallography clarify the progress of the restoration mechanism and the influence of solutes, precipitates and inclusions. The ductility is related to how the softening mechanisms delay the fracture mechanisms ssmming from the alloy structure. The rate of static softening after hot deformation is determined by comparing the yield stress on reloading after an interval to that before it; many measurements for different times can be carried out on a single specimen by recrystallizing it between each stage in the torsion apparatus. The physical simulation of rolling schedules having many passes with declining temperature and rising strain rate is possible on computerized machines
oai:ojs.www.fracturae.com:article/975
2013-09-06T12:17:45Z
MST:ART
v2
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2013-09-06T12:17:45Z
Metallurgical Science and Tecnology
Vol. 9 No. 3 (1991)
A preliminary study on fracture mechanics tests in the presence of V-notches
Sirtori, S.
Gorla, C.
Guagliano, M.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/975
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oai:ojs.www.fracturae.com:article/976
2013-09-06T12:17:45Z
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2013-09-06T12:17:45Z
Metallurgical Science and Tecnology
Vol. 9 No. 3 (1991)
A procedure for the evoluation of microalloyed steel applications in case of components subjected to repeated impulsive loads
Blarasin, A.
Caffa, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/976
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oai:ojs.www.fracturae.com:article/977
2013-09-06T12:17:45Z
MST:ART
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2013-09-06T12:17:45Z
Metallurgical Science and Tecnology
Vol. 9 No. 3 (1991)
Evaluation of the mechanical behaviour of a beta-C titanium alloy in aged and overaged conditions
Buttinelli, D.
Felli, F.
Festa, G.B.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/977
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oai:ojs.www.fracturae.com:article/978
2013-09-06T12:17:45Z
MST:ART
v2
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2013-09-06T12:17:45Z
Metallurgical Science and Tecnology
Vol. 9 No. 3 (1991)
Evaluation of the mechanical behaviour of a beta-C titanium alloy in aged and overaged conditions
Moschini, R.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/978
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oai:ojs.www.fracturae.com:article/979
2013-09-06T12:17:45Z
MST:ART
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2013-09-06T12:17:45Z
Metallurgical Science and Tecnology
Vol. 9 No. 3 (1991)
Vacuum plasma-arc metallization and dielectrics
Grinchenko, V.T.
Ivanovsky, B. F.
Kapralova, N.A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/979
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oai:ojs.www.fracturae.com:article/980
2013-09-06T12:17:52Z
MST:ART
v2
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2013-09-06T12:17:52Z
Metallurgical Science and Tecnology
Vol. 10 No. 1 (1992)
Single-crystal casting of nickel-base superalloys by directional rapid solidification
Shalin, R. E.
Pankratov, V. A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/980
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oai:ojs.www.fracturae.com:article/981
2013-09-06T12:17:52Z
MST:ART
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2013-09-06T12:17:52Z
Metallurgical Science and Tecnology
Vol. 10 No. 1 (1992)
The deformation of Aluminium-Magnesium alloys
Nasr el-din, H.
Moustafa, S.F.
Abdel-Azim, A.N.
Ismail, A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/981
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oai:ojs.www.fracturae.com:article/982
2013-09-06T12:17:52Z
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2013-09-06T12:17:52Z
Metallurgical Science and Tecnology
Vol. 10 No. 1 (1992)
Thermal effects during plastic flow in nickel-base superalloys
Lisiecki, B.
Kubin, L.
Estrin, Y.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/982
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oai:ojs.www.fracturae.com:article/983
2013-09-06T12:18:35Z
MST:ART
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2013-09-06T12:18:35Z
Metallurgical Science and Tecnology
Vol. 10 No. 3 (1992)
Experimental investigation of Barkausen noise variations during the fatigue life of steel specimens
DOnzella, G.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/983
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oai:ojs.www.fracturae.com:article/984
2013-09-06T12:18:35Z
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2013-09-06T12:18:35Z
Metallurgical Science and Tecnology
Vol. 10 No. 3 (1992)
Laser repairing techniques for superalloy components
Balbi, M.
Brachetti, M.
Angelo, D. D.
Gallo, C.
Mor, G.P.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/984
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oai:ojs.www.fracturae.com:article/985
2013-09-06T12:18:35Z
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2013-09-06T12:18:35Z
Metallurgical Science and Tecnology
Vol. 10 No. 3 (1992)
Physical and chemical processes in the production of Aluminium-SiC whiskers composites by squeeze-casting
Shalin, R.
Gribkov, A.
Salibekov, S.
Abuzin, J.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/985
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oai:ojs.www.fracturae.com:article/986
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2013-09-06T12:18:35Z
Metallurgical Science and Tecnology
Vol. 10 No. 3 (1992)
Superplastic forming (SPF) of materials and SPF combined with diffusion bonding: technological and design aspects
Ceschini, L.
Afrikantov, A.
2013-08-09
url:https://www.fracturae.com/index.php/MST/article/view/986
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oai:ojs.www.fracturae.com:article/987
2013-09-06T12:18:41Z
MST:ART
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2013-09-06T12:18:41Z
Metallurgical Science and Tecnology
Vol. 11 No. 1 (1993)
Field criteria for failure analysis: first experimental results on V-notched specimens
Sirtori, S.
Gorla, C.
Guagliano, M.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/987
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oai:ojs.www.fracturae.com:article/988
2013-09-06T12:18:41Z
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2013-09-06T12:18:41Z
Metallurgical Science and Tecnology
Vol. 11 No. 1 (1993)
High temperature structural materials for gas turbines
Campo, E.
Lupinc, V.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/988
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oai:ojs.www.fracturae.com:article/989
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2013-09-06T12:18:41Z
Metallurgical Science and Tecnology
Vol. 11 No. 1 (1993)
High temperature ai oxidation of 22 Cr 11-19 Ni steels
Bernabai, U.
Cavallini, M.
Felli, F.
Tamba, A.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/989
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2013-09-06T12:18:41Z
Metallurgical Science and Tecnology
Vol. 11 No. 1 (1993)
Map of residual strain in a welded AISI 304 steel component, obtained by neutron diffraction
Albertini, G.
Ceretti, M.
Coppola, R.
Ghia, S.
Lodini, A.
Marinani, P.
Perrin, M.
Rustichelli, F.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/990
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oai:ojs.www.fracturae.com:article/991
2013-09-06T12:18:41Z
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2013-09-06T12:18:41Z
Metallurgical Science and Tecnology
Vol. 11 No. 1 (1993)
Monotonic and cyclic stress-strain behaviour of high strength steel
Hussain, K.
De Los Rios, E. R.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/991
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2013-09-06T12:18:48Z
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2013-09-06T12:18:48Z
Metallurgical Science and Tecnology
Vol. 11 No. 2 (1993)
Comparative evaluations of malleable and ductile iron connecting rods
Giugni, P.
Sarietto, G.
Magistrali, G.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/992
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Metallurgical Science and Tecnology
Vol. 11 No. 2 (1993)
Effect of chromium on the diffusion rate of aluminium on Fe-Cr-Ni alloys
Alderisio, A.
Brevaglieri, B.
Natali, S.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/993
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Metallurgical Science and Tecnology
Vol. 11 No. 2 (1993)
Recrysallization behaviour of hot rolled aluminium 3004 alloy
Lee, F. T.
2013-08-30
url:https://www.fracturae.com/index.php/MST/article/view/994
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