In this work, the effect of superimposing of isothermal low cycle fatigue loading to the thermomechanical fatigue loading on the crack propagation behavior of the naturally initiated short crack in Low-carbon nitrogen-controlled 316 stainless steel was investigated. The experimental results indicated that the crack propagation path depends on the loading condition; the cracks appear to be initiated and propagated at grain boundary perpendicular to the loading axis which might be a relatively week region at elevated temperature under the in-phase type TMF loading and the LCF loading at high temperature, on the other hand, the cracks initiated and propagated by the transgranular mode under the out-of-phase type TMF loading and the LCF loading at middle temperature. The short crack growth rate has also affected the microstructure, i.e., the intergranular crack exhibits higher growth rate compared with the transgranular crack. In addition, the crack growth rate was accelerated by superimposing of the isothermal low cycle fatigue loading to the main thermo-mechanical fatigue loading. The short crack growth rate could be predicted according to summation law of crack growth behavior based on the J-integral approach considering with crack propagation path.
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors are allowed to retain both the copyright and the publishing rights of their articles without restrictions.
Open Access Statement
Frattura ed Integrità Strutturale (Fracture and Structural Integrity, F&SI) is an open access journal which means that all content is freely available without charge to the user or his/her institution. Users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles in this journal without asking prior permission from the publisher or the author. This is in accordance with the BOAI definition of open access. F&SI operates under the Creative Commons Licence Attribution 4.0 International (CC-BY 4.0). This allows to copy and redistribute the material in any medium or format, to remix, transform and build upon the material for any purpose, even commercially, but giving appropriate credit and providing a link to the license and indicating if changes were made.