在3 kW横流CO2激光器上,对低碳钢表面进行镍基和钴基合金激光熔覆试验研究时发现,加入不同种类适量的稀土氧化物,对熔覆层的结晶组织有明显的粗化作用, 同时可使熔覆层的抗热震性提高10倍以上。显然, 这对髙温或急冷急热工况条件下激光熔覆技术的应用与研究具有重要意义。文中对稀土影响熔覆层晶粒度的原因进行了理论分析,论述了稀土改善熔覆层的抗热震性能的作用机理。

Laser cladding experiment of nickel base alloy and cobalt base alloy on the Q235 steel was done with a 3 kW transversely flow CO2 laser. It was discovered that suitable rare-earth oxide additives promoted size of crystallites in the cladding layer to coarsen obviously, and thermal shock resistance of the layer rose by over 10 times, which is quite important to the application and study of laser cladding technology at high temperature or thermal shock situation. Mechanisms about effect of on the laser cladding layer were discussed in this paper.