航空发动机机匣焊接模拟与残余应力控制

Numerical Simulation of Welding Psocess of Case Shell on Aero Engine and Its Residual Stress Control

利用有限元软件SYSWELD模拟航空发动机机匣部件的焊接过程和焊后局部热处理过程,研究焊后局部热处理对焊接残余应力的影响。结果表明:复合热源模型"双椭球热源+3D高斯体热源"模拟出的椭圆波扫描电子束焊的熔池形貌和试验结果十分吻合;椭圆波扫描电子束焊温度峰值为2543℃,超过材料熔点,热处理温度峰值为1200℃,达到材料相变点;焊后局部热处理过程可使机匣的残余应力显著降低。

The process of electron beam welding and local heat treatment was simulated by finite element software SYSWELD in case shell on aero engine, the influence of local heat treatment on welding residual stress was studied. The results show that the simulation results of weld pool morphology of elliptical wave scanning electron beam welding by using the composite heat source model of the double ellipsoid heat source ＋3D Gauss body heat source are in good agreement with the experimental results; The temperature peak value of elliptical wave scanning electron beam welding is 2543℃, which is over the material melting point, and the temperature peak value of local heat treatment is 1200℃, which reaches material phase change point. The process of local heat treatment can markedly reduce the residual stress in case shell on aero engine.