铍材激光钎焊温度场和应力场的数值模拟

在综合考虑激光钎焊熔池表面形状和几何参数的基础上,建立了适合于铍材激光钎焊的表面双椭圆热源分布模型;通过对数值模拟与试验获得的熔深、熔宽等参数的对比,可知计算结果与试验结果吻合较好,说明双椭圆表面热源模型能够较好地模拟铍环钎焊.通过对焊接加热和冷却过程中铍环焊缝附近应力状态变化的比较,发现凝固过程中最大轴向拉应力和最大环向拉应力均位于焊缝中心,这正是焊缝中心较易形成凝固裂纹的主要原因.

Numerical Simulation of Welding Temperature and Stress Fields during Laser Brazing Process of Beryllium

Based on the superficial shape and geometry parameters of molten bath during laser brazing process,the heat distribution of surface bielliptic model was established to simulate the laser brazing process of beryllium ring.The results show that the simulated depth and width were consistent with experimental results and the model could simulate the laser brazing process of beryllium accurately.A comparison of the stress state change of internal and outside surface in heating and cooling process indicated that ...