激光熔覆的热力学计算及显微硬度分析

Thermodynamic Calculation and Microhardness Analysis of Laser Cladding

激光熔覆是推动我国再制造行业发展的关键技术,熔覆层内部的能量转换方式及显微硬度的分布是影响熔覆层性能与质量的重要因素。分别采用不同的工艺参数在45钢表面进行激光熔覆实验,并对激光熔覆进行了热力学分析,得出了粉末吸收的能量与温度变化量之间的关系,并对不同工艺参数下熔覆层的纵向显微硬度进行分析。结果表明,粉末材料所吸收能量随着粉末材料温度变化量的增大而增大;不同工艺参数条件下的纵向显微硬度曲线均呈连续分布,该种分布说明熔覆层的内部应力较小,熔覆层与基体易于形成良好的冶金结合。

Laser cladding is key technology to promote the development of China's remanufacturing industry.Energy conversion mode and distribution of microhardness are important factors affecting the performance and quality of the cladding layer.Laser cladding experiment was implemented on 45 steel surface with different processing parameters,and the thermodynamic analysis of laser cladding was studied.The relationship between energy absorbed by the powder and the amount of temperature change was obtained,and the vertical direction microhardness of the cladding layer under different processing parameters was analyzed.The results show that the energy absorbed by powder material increase by increasing the amount of temperature change,and the vertical direction microhardness under different processing parameters are continuous distribution.This kind of distribution indicates that internal stress of the cladding layer is small,and the cladding layer and the substrate are easy to form well metallurgical combination.