He Peng, Wu Yunxin, Zhang Tao, Jin Junlong
Light Alloy Research Institute, Central South University, Changsha 410083, China.
State Key Laboratory of Precision Manufacturing for Extreme Service Performance, Changsha 410083, China.
Materials (Basel). 2024 Sep 13;17(18):4507. doi: 10.3390/ma17184507.
Residual stresses with a complex distribution are generated after linear friction welding, which affects the service performance of the weldment. In this work, a numerical model for linear-friction-welded Ti17 (Ti-5Al-2Sn-2Zr-4Mo-4Cr) was developed to investigate the evolution of residual stresses and the effect of welding parameters on residual stresses. Additionally, a method for predicting internal residual stresses was constructed. The results indicate that the residual stresses near the contact interface are largest in the oscillatory direction, peaking at ~661 MPa at 2 mm away from the contact interface. The evolution of stresses is not only related to the inhomogeneous thermal gradient, but also to the forging force. And the stress distribution essentially stabilizes within the duration of the forging force applied. Increasing the amplitude and frequency results in higher peaks of tensile residual stresses and a more concentrated distribution. Conversely, increasing the forging force only reduces the magnitude of the residual stresses. The developed prediction method, based on the similarity of internal residual stress distributions, facilitates the prediction of internal residual stresses using measured surface residual stresses.
线性摩擦焊接后会产生分布复杂的残余应力，这会影响焊件的使用性能。在这项工作中，开发了一个线性摩擦焊接Ti17（Ti-5Al-2Sn-2Zr-4Mo-4Cr）的数值模型，以研究残余应力的演变以及焊接参数对残余应力的影响。此外，构建了一种预测内部残余应力的方法。结果表明，接触界面附近的残余应力在振动方向上最大，在距接触界面2mm处达到峰值，约为661MPa。应力的演变不仅与不均匀的热梯度有关，还与锻造力有关。并且应力分布在施加锻造力的持续时间内基本稳定。增加振幅和频率会导致拉伸残余应力的峰值更高且分布更集中。相反，增加锻造力只会降低残余应力的大小。所开发的基于内部残余应力分布相似性的预测方法，便于利用测量的表面残余应力来预测内部残余应力。
