Study on the effects of ultrasonic impact treatment on the local mechanical properties of welded joints based on the digital image correlation

• Published in: Measurement : journal of the International Measurement Confederation 2025-01, Vol.239, p.115441, Article 115441
• Main Authors: Gu, Bangping, Zhuo, Jingshu, Xu, Guanhua, Gao, Liqiang
• Format: Article
• Language: English
• Subjects: Digital image correlation (DIC); Ultrasonic impact treatment (UIT); Welded joint
• ISSN: 0263-2241
• DOI: 10.1016/j.measurement.2024.115441

•The order of yield strength improvement of each region by UIT is WM>HAZ>BM.•The order of UIT to improve the tensile strength of each region is BM>HAZ>WM.•After UIT, the yielding plateau of the material significantly shortens.•After UIT, the increase in the strength coefficient of the HAZ is the highest.•The hierarchy of the local strain inhibition effect is as follows: BM>HAZ>WM. In this study, UIT was used to strengthen the local mechanical properties of welded joints, and the influence of UIT on the local mechanical properties of welded joints was analyzed by 3D-DIC technology. At the same time, the mechanism of UIT on the microstructure and properties of welded joints was revealed by microstructure observation. By measuring the full-field strain process of the welded joint after UIT under uniaxial tensile load, the curve of the strain in the local area with time is obtained. At the same time, the Ramberg-Osgood equation and Considère criterion are used to fit the material constitutive relationship at each point in the local area. The results show that UIT significantly improves the yield strength of the WM and the tensile strength of the BM. This study provides technical and theoretical support for the preparation of high-quality welded joints by UIT technology.