激光熔覆技术制备新型Al-TiC复合涂层的研究

摘要

采用预置激光熔覆技术,将Al-Ti-C混合粉末预置于铝合金基体表面,并在氩气保护下,利用YAG激光器实现了在铝合金表面原位形成Al -TiC复合熔覆层.通过改变激光束能量密度和激光束扫描速度等工艺参数,获得了不同工艺条件下的激光熔覆层,并对其显微组织、物相分布及耐磨性能进行比较研究.结果表明由于激光能量密度和激光束扫描速度不同,所形成的熔覆层中TiC的分布状态有很大差别.随着激光能量密度的增大,TiC分布趋于均匀.当激光束扫描速度为2.5mm/s、激光束能量密度为6.09 J/mm2时,熔覆层具有最高的耐磨性能.%Al-Ti-C mixed powder was preset on the surface of aluminum alloy substrate by using pre-laser cladding technology, and then Al-TiC cladding composite coating was formed on aluminum alloy surface by using YAG laser under argon protection. Laser cladding layers could be prepared under different energy density, scanning speed of laser beam and other processing parameters. It is showed that under different energy density and scanning speed of the laser beam,TiC distribution in the cladding layer varied greatly. With the increase of energy density,TiC distribution would become in a more uniformed state. When the scanning speed and energy density of laser beam were 2. 5 mm/s and 6. 09 J/m separately, the cladding layer had the best wear resistance.