多道次激光熔覆温度场与应力场有限元分析
Finite Element Analysis on Temperature and Stress Field of Multi-track Laser Cladding
鲁凤莲
作者单位：(威海职业学院 船舶工程系, 山东 威海 264209)
中文关键字：有限元分析； 多道熔覆； 应力场； 横向裂纹
英文关键字：finite element analysis; multi-track cladding; stress field; transversal crack
中文摘要：利用ANSYS软件，基于遗传算法和神经网络对多道激光熔覆温度场和应力场进行有限元分析，发现多道熔覆过程中，温度场椭圆偏向已形成熔覆层的一侧；多道熔覆前面道次的熔覆相当于对后续的熔覆有预热作用；熔覆层纵向应力最大，横向应力次之，厚度方向应力最小；而熔覆层中心一直处于拉应力状态；纵向拉应力高出横向和厚度方向应力几倍，并且在熔覆层与基体结合区域达到最高值。因此推断横向裂纹是最主要的裂纹形式，而且熔覆层心部或与基体结合区是裂纹高发区，这与试验结果相吻合。
英文摘要：Basing on genetic algorithm and neural network, the finite element analysis on the temperature fields and stress fields of multi-track laser cladding was carried out using ANSYS software. The results show that, in the multi-track cladding process, the temperature field ellipse leans to the formed cladding, the front cladding has preheating function to the following cladding. In the cladding, the longitudinal stress is biggest, the lateral stress is second, and the thickness direction stress is smallest. The center of the cladding is in the tensile stress condition. The longitudinal tensile stress is several times higher than the lateral and thickness direction stress, and the tensile stress achieves the maximum in the area of joint between the cladding and substrate. Therefore it is inferred that transversal crack is the most main crack form in multi-track laser cladding, moreover the joint between cladding and substrate is crack sensitive area, and this is consistent with actual experiments.