金属材料激光相变硬化的三维数值模拟

A Three-dimensional Numerical Model for Laser Transformation Hardening of Metals

给出了用有限差分法对金属材料激光相变硬化过程建立的三维数值模型。模型考虑了工件有限尺度、工件材料热物理性质的温度依赖关系、激光处理参数以及对流、辐射造成的表面热损失．根据模型可以得出工件表面和内部任意部位的三维温度分布像，可以预测激光处理的相变层深，并据此优化激光处理参数的选定．通过对一种锆合金的激光相变硬化实验，验证了所得结果与模型理论计算的一致．

A three-dimensional numerical model for laser surface transformation hardening of metals using the finite differential technique is given in this peper. The model takes into account the finite dimensions of the workpiece, the temperature dependence of thermalPhysical properties of the material, the laser processing parameters, and the surface heat losses due to convection and radiation. According to the model a three- dimensional temperature distribution on the surface and inside the workpiece can be obtained. The model can also be used to predict the phase transformation depth resulting from the laser surface treatment. Good agreement is demonstrated with experimental results for laser hardening of a zirconium alloy.