为了解决热作模具表面磨损并导致失效的问题,基于ANSYS APDL软件,采用数值模拟的方式在热作模具上施加高斯热源,并利用生死单元法将H13合金粉末进行熔覆。通过温度场和应力场对工艺参数进行优化选择,对优化后的工艺参数进行实验验证,并对涂层进行了性能检测。结果表明,所选参数范围内的模拟最优参数为激光功率1200 W,扫描速率12 mm/s,模拟结果与实际涂层的形貌和温度分布较为接近; 数值模拟中的热影响区以及结合区与实验制备的结果高度一致; 测量熔覆层的深度为0.13 mm,与模拟得到的深度为0 mm~0.2 mm相应证,进一步说明了模拟结果的可靠性; 熔覆层的硬度以及耐磨性得到极大的提升,分别是基体的3倍和28倍以上。此研究结果为强化和修复热作模具提供了参考。

For the sake of solving the problem of surface wear and failure of the hot work die, based on ANSYS APDL software, a Gaussian heat source was applied to the hot work die by numerical simulation, and the H13 alloy powder was clad by the life and death element method. The process parameters were optimized and selected through the temperature field and stress field. The optimized process parameters were tested and verified, and the performance of the coating was tested. The results show that the optimal simulation parameters within the selected parameter range are the laser power of 1200 W and the scanning speed of 12 mm/s. The simulation results are close to the morphology and temperature distribution of the actual coating. The heat-affected zone in the numerical simulation and the combination of the results are highly consistent with the experimentally prepared results; the measured depth of the cladding layer is 0.13 mm, which corresponds to the simulated depth of 0 mm~0.2 mm, which further illustrates the reliability of the simulation results; the hardness and wear resistance of the cladding layer have been greatly improved, which are 3 times and 28 times more than that of the matrix, respectively. The results of this study provide a reference for strengthening and repairing hot work molds.