模具钢表面超声辅助激光熔覆Ni60合金涂层的仿真与实验分析

Simulation and experimental analysis of ultrasonic assisted laser cladding Ni60 alloy coating on die steel

采用超声辅助激光熔覆技术在H13热作模具钢表面制备镍基合金涂层,通过COMSOL仿真软件建立分析模型,探究超声频率对熔覆层温度及温度梯度的影响规律,并通过实验探究超声频率对宏观形貌以及显微组织的影响。结果表明:随着超声频率的增加,熔覆层温度逐渐增加,而温度差值呈先减小后增大的趋势;随着超声频率的增加,沿熔覆层切面纵向温度呈上升趋势,其温度差值呈先增大后减小的趋势;施加超声的熔覆层比未施加超声的温度梯度小,且超声频率越大,温度梯度越小;随着超声频率的增大,稀释率增大,熔覆层熔宽与熔深增大;超声频率越高,晶粒分离及细化程度越好;超声促进熔覆层与基体中元素扩散,改善元素偏析。

The Ni-base alloy coating was prepared on H13 steel by ultrasonic assisted laser cladding technology.The analysis model was established by COMSOL simulation software to explore the influence of ultrasonic frequency on the temperature and temperature gradient of the cladding layer,and the influence of ultrasonic frequency on the macroscopic morphology and microstructure was explored through experiments.The results show that the temperature of the cladding layer increases with the increase of ultrasonic frequency,while the temperature difference decreases first and then increases.With the increase of ultrasonic frequency,the longitudinal temperature along the cladding plane increases,and the temperature difference increases first and then decreases.The temperature gradient of cladding layer with ultrasonic application is smaller than that without ultrasonic application,and the temperature gradient decreases with the increase of ultrasonic frequency.With the increase of ultrasonic frequency,the dilution rate increases,and the cladding width and depth increase.The higher the ultrasonic frequency,the better the grain separation and refinement;Ultrasonic promotes element diffusion between cladding layer and matrix and improves element segregation.