目的 对磨损后的高速列车制动盘进行修复，以降低列车运营成本。方法 采用机械自混粉末，利用激光熔覆工艺制备 CrMnFeCoNi 高熵合金熔覆层对制动盘进行修复，对熔覆层组织、组成相、耐磨性和耐腐蚀性进行研究。结果 最佳实验工艺为：激光功率 1000 W，扫描速度 5 mm/s，送粉电压 7.5 V，对应单道宽度 2.42 mm，高度 0.44 mm，搭接率 50%。激光熔覆过程中存在烧损，造成粉末成分不是等摩尔原子比，最终熔覆层组成相为 BCC 和 FCC 两相。熔覆层铸造组织较均匀，生长方向趋于一致，存在一定数量的非晶和纳米级组织。CrMnFeCoNi 高熵合金熔覆层可降低材料磨损量，摩擦系数为 0.3655，更耐磨；腐蚀电流密度为 1.24×10?5 A/cm2，腐蚀速率为 0.146 475 mm/a。结论 通过激光熔覆工艺制备的高速列车制动盘高熵合金修复层，其耐磨性、耐腐蚀性均优于基体，延长了磨损后制动盘的使用寿命，满足制动盘使用要求。

The work aims to repair the worn high-speed train brake disc to reduce train operating cost. The CrMnFeCoNi high entropy alloy prepared with mechanical self-mixing powder by laser cladding was used to repair the brake disc and study the microstructure, composition phase, wear resistance and corrosion resistance. The best experimental technology was laser power of 1000 W, scanning speed of 5 mm/s, feeding voltage of 7.5 V, single channel width of 2.42 mm, single channel height of 0.44 mm and single overlap rate of 50%. There was burning loss in the process of laser cladding, so the powders composition was not equal to molar atom ratio and finally BCC and FCC phases were formed in CrMnFeCoNi high entropy alloy cladding layer. The casting microstructure of the cladding layer was uniform with the same growth tendency and certain amorphous and nanometer microstructures. The CrMnFeCoNi high entropy alloy reduced the wear by the friction factor of 0.3655, so the high entropy alloy cladding layer was more wear-resisting. The high entropy alloy cladding layer current density was 1.24?10?5 A/cm2 and the annual corrosion rate thickness was 0.146 475 mm/a. The high entropy alloy repair layer of high-speed train brake disc prepared by laser cladding has better wear resistance and corrosion than the matrix and the service life of worn brake disc is extended to meet the demand of brake disc.