本文叙述了采用两千瓦级CO_2激光器对铬钼镍合金铸铁、球墨铸铁及激冷铸铁等几种材料进行激光表面处理的实验研究和结果。探讨了处理前的预处理、不同的功率密度、扫描速度及光斑尺寸对激光硬化的影响。对采用相变硬化和熔化-凝固硬化的激光处理前后的金相组织的特点,进行了对比和分析。此外。对激冷铸铁在激光处理时产生的裂纹作了初步的探讨。 This paper describes the experimental research and results of laser surface treatment of several materials, such as chrome molybdenum-nickel-iron alloy cast iron, ductile iron and chilled cast iron, using a two-kilowatt CO2 laser. The effects of pre-treatment, different power density, scanning speed and spot size on laser hardening were discussed. The characteristics of the microstructure before and after laser treatment with phase change hardening and fusion-setting hardening were compared and analyzed. In addition. The preliminary research on the crack produced by laser processing of chilled cast iron was made.