A recent study from Southwest Jiaotong University looked at ultrasonic impact treatment to improve stress corrosion cracking resistance of welded joints of aluminum alloy. Principal engineer from EWI, Yu-Ping Yang, was the co-author of the article, which was published in the Journal of Materials Engineering and Performance (JMEP). In a paper entitled Ultrasonic Impact Treatment to Improve Stress Corrosion Cracking Resistance of Welded Joints of Aluminum Alloy, Yu-Ping and colleagues from Southwest Jiaotong University in China addressed the significant problem of stress corrosion cracking of welded joints of 6005A-T6 aluminum alloy in high-speed trains. In the study, ultrasonic impact treatment was applied successfully to control the residual stress of the welded joints of 6005A-T6 aluminum alloy. Their study showed that ultrasonic impact treatment can induce compressive longitudinal and transverse residual stress in the welded joint, harden the surface, and increase the tensile strength of welded joints. Their study also shows the surface of ultrasonic impact-treated samples had far fewer corrosion pits than that of an untreated sample.