Mai Chunliang, Hu Xue, Zhang Lixin, Song Bao, Zheng Xiongfei
College of Mechanical and Electrical Engineering, Shihezi University, Shihezi 832003, China.
College of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
Materials (Basel). 2022 Jan 28;15(3):1044. doi: 10.3390/ma15031044.
It is well known that welding dissimilar metals can play the advantages and characteristics of those different metals, but it is easy to encounter some problems. In this paper, the thermomechanical behavior of the weldolet-branch dissimilar steel joints in different welding cases is analyzed by establishing a three-dimensional finite element model, and the predicted thermal cycling and residual stresses are verified using experimental tools. The results show that the high temperature area and the heat affected zone on the side of the branch pipe are larger, and there is a large stress gradient at the fusion line on both sides of the weld. Too high or too low temperature between welding layers will cause large residual stress, thus, 200 °C is more suitable for the welding of weldolet-branch joints. The residual stresses of path-1, path-2 and path-3 have similar distributions at 0° and 180° sections, and the circumferential and axial residual stresses on the inner surface are larger than those on the outer surface. The residual stress on the inner and outer surfaces of path-3 is smaller than that of path-1 and path-2 at the 90° and 270° sections as a whole, and the residual stress at the 90° section reaches the minimum.
众所周知，焊接异种金属可以发挥不同金属的优势和特性，但容易遇到一些问题。本文通过建立三维有限元模型，分析了不同焊接工况下异钢承插焊接接头的热机械行为，并使用实验工具对预测的热循环和残余应力进行了验证。结果表明，支管一侧的高温区域和热影响区较大，焊缝两侧熔合线处存在较大的应力梯度。焊层间温度过高或过低都会产生较大的残余应力，因此，200℃更适合异钢承插焊接接头的焊接。路径1、路径2和路径3在0°和180°截面处的残余应力分布相似，内表面的周向和轴向残余应力大于外表面。路径3在90°和270°截面处的内、外表面残余应力整体小于路径1和路径2，且90°截面处的残余应力达到最小值。
