钛/铝异种合金激光-电弧复合熔钎焊接头残余应力数值计算

Numerical simulation on residual stress of Ti/Al dissimilar joint by laser-arc hybrid welding-brazing

采用Abaqus有限元分析软件进行了Ti-6A1-4V钛合金与6061铝合金的激光-电弧复合熔钎焊接头残余应力的数值计算,结合X射线衍射法对计算结果进行验证。结果表明,钛合金侧及铝合金侧Mises等效残余应力呈现非对称分布,焊缝中心处应力值最大;横向残余应力沿焊缝长度方向表现为"两端受压,中间受拉"的分布特征,端部压应力峰值接近200 MPa;铝合金侧纵向残余应力分布存在拉应力向压应力转变的过渡区域;正反面余高处存在应力集中现象,试板焊后出现翘曲变形。

In this paper, the residual stress in Ti-6 A1-4 V/6061 dissimilar joint by laser-arc hybrid welding-brazing process was numerically simulated using Abaqus, the validation of the numerical simulation was verified by X-ray diffraction method. The results showed that the Von Mises stress of the titanium alloy side and the aluminum alloy side was found to be asymmetric, the highest residual stress was distributed in the weld center. Distribution of transverse stress in parallel line of weld seam indicated that the middle region was subjected to tensile stress and the end region was subjected to compressive stress, the peak compressive stress was close to 200 MPa. Distribution of longitudinal residual stress on the aluminum alloy side had a transition region from tensile stress to compressive stress. There was stress concentration in reinforcement of the joint, and the test plate demonstrated warp distortion after welding.