Residual stress evaluation in friction stir welding of aluminum plates by means of acoustic emission and ultrasonic waves

Sadeghi, S.; Zarif Karimi, N.; Fotouhi, M.; Hasani, M.; Najafabadi, M. Ahmadi; Pavlovic, A.

Abstract

© Faculty of Mechanical Engineering, Belgrade. The residual stress assessment in structures is essential for optimization of the structures' design. The attention of this paper is focused on how acoustic emission signals caused by tensile loading of the friction stir welded aluminum plates are expected to vary depending upon the residual stress. To this aim, the distribution of residual stresses in two friction stir welded aluminum specimens was firstly evaluated by ultrasonic stress measurement. AE signals were then produced during tensile tests and captured using AE sensors. The obtained AE signals were analyzed using statistical features including crest factor, cumulative crest factor and sentry function. It was found that the crest factor could be used to identify the presence of the residual stresses and that the trends of sentry function are in good agreement with the results of crest factor and cumulative crest factor.

• Journal Article Type: Article
• Acceptance Date: Dec 28, 2017
• Publication Date: Jan 1, 2018
• Deposit Date: Feb 21, 2018
• Publicly Available Date: Feb 21, 2018
• Journal: FME Transactions
• Print ISSN: 1451-2092
• Electronic ISSN: 2406-128X
• Publisher: University of Belgrade
• Peer Reviewed: Peer Reviewed
• Volume: 46
• Issue: 2
• Pages: 230-237
• DOI: https://doi.org/10.5937/fmet1802230S
• Keywords: residual stress, acoustic emission, ultrasonic stress; measurement, sentry function, crest factor, friction stir welding
• Public URL: https://uwe-repository.worktribe.com/output/875811
• Publisher URL: http://www.mas.bg.ac.rs/istrazivanje/fme/start
• Contract Date: Feb 21, 2018