Liu Yizhou, Huang Wenhua, Yu Banhai, Chen Zhihao, Wang Ping
School of Ocean Engineering, Harbin Institute of Technology at Weihai, Weihai 264209, China.
Wuhan 2nd Ship Design and Research Institute, Wuhan 430200, China.
Materials (Basel). 2023 Sep 13;16(18):6196. doi: 10.3390/ma16186196.
This study aims to assess the effect of ultrasonic impact treatment (UIT) on the exterior weld seam of S355J2 T-joints used in orthotropic steel bridge decks. The microstructure and mechanical behavior of T-joints after UIT was investigated in this study. Fatigue tests of T-joints before and after UIT were performed. The stress concentration at the interior and exterior weld toe of T-joints was considered using the traction structural stress method. The results showed that hardness increases by 10% due to the localized grain refinement caused by UIT. UIT significantly improves the fatigue life of T-joint specimens by 350% and 150% at stress ratios of 0.1 and 0.3, respectively. As the transition angle between the weld profile and the base metal profile increases, the stress concentration factor decreases.
本研究旨在评估超声冲击处理（UIT）对正交异性钢桥面板中使用的S355J2 T型接头外部焊缝的影响。本研究调查了超声冲击处理后T型接头的微观结构和力学行为。对超声冲击处理前后的T型接头进行了疲劳试验。采用牵引结构应力法考虑T型接头内部和外部焊趾处的应力集中。结果表明，由于超声冲击处理引起的局部晶粒细化，硬度提高了10%。在应力比分别为0.1和0.3时，超声冲击处理显著提高了T型接头试样的疲劳寿命，分别提高了350%和150%。随着焊缝轮廓与母材轮廓之间的过渡角增大，应力集中系数减小。
