Cold expansion by hardening is a common process used in the aerospace industry to extend the fatigue lifetime of assembly holes, through a field of high compressive tangential residual stresses. The understanding and the control of the residual stresses are thus important, since it can be beneficial to improve lifetime of the structures. The main objective of this work is to establish and validate a predictive model of residual stresses generated by cold hardening. This technique can be an effective ways for industrials allowing an estimation of the fatigue lifetime of parts according to the process parameters or to determine the optimal parameters to maximize fatigue lifetime. An experimental setup was used to highlight the effect of expansion degree, thickness of the part and yield strength on the residual stresses profiles. Moreover, the proposed mathematical models were used to determine the optimal values of the various factors for the residual stress profiles prediction at any factor values, in order to achieve maximum service life after repair of a cracked structure or to delay crack initiation and growth in riveted or bolted structures. Besides, the modelling permits us to highlight the effect of interaction of these factors on the residual stresses profiles.
How to Cite
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.