目的 通过与激光熔覆进行对比，探究高速激光熔覆铁基TY-2合金的显微组织及力学性能。方法 采用高速激光熔覆技术在27SiMn不锈钢基体上制备铁基TY-2合金熔覆层。利用扫描电子显微镜、X射线衍射仪、显微硬度计，对熔覆层的显微组织、物相结构及力学性能进行分析测试，对比研究高速激光熔覆与激光熔覆铁基TY-2合金熔覆层的显微组织和力学性能。结果 与激光熔覆层相比，获得的高速激光熔覆层均匀致密，无裂纹，孔隙与夹杂较少，与基体形成良好的冶金结合。激光熔覆层的组织以粗大的柱状晶为主，高速激光熔覆层的组织以尺寸为5~10 μm的细小晶粒为主。高速激光熔覆层与原始粉末的物相一致，包含(Fe,Ni)、Cr0.19Fe0.7Ni0.11和Fe-Cr等相。激光熔覆层与原始粉末的物相有所差别，高能量密度导致CaNi3C0.5金属间化合物的生成。高速激光熔覆层的平均硬度为604HV0.3，相比激光熔覆层(543HV0.3)提高了9.4%。结论 高速激光熔覆的总能量较低，为激光熔覆总能量的77.9%，其中高速粒子携带的动能占高速激光熔覆总能量的17.7%。高速激光熔覆可实现低能量下的高效熔覆，熔覆层的组织更加细小，成分更加均匀，硬度更高。

The work aims to explore the microstructure and mechanical properties of high-speed laser cladding Fe-based TY-2 alloy coatings, compared with the conventional laser cladding. The Fe-base TY-2 alloy coating was prepared on 27SiMn steel substrate by high-speed laser cladding technique. The scanning electron microscope, X-ray diffractometer and microhardness tester were used to analyze the microstructure, phase structure and mechanical properties of the high-speed laser cladding coating and laser cladding coating. Compared with the coating of laser cladding, the coating of high-speed laser cladding was uniformly dense, without cracks, with fewer impurities, and demonstrated a good metallurgical bonding with the substrate. The microstructure of the laser cladding coating was composed of mainly columnar crystal, while high-speed laser cladding coating consisted of mainly fine grain with the size of 5~10 μm. The phase of high-speed laser cladding coating was consistent with the original powder, including (Fe,Ni), Cr0.19Fe0.7Ni0.11, Fe-Cr, etc. Whereas, the phase of laser cladding coating differed from the original powder, and the high energy density led to the formation of CaNi3C0.5 intermetallic compounds. The average hardness of high-speed laser cladding coating was 604HV0.3, which is 9.4% higher than that of laser cladding coating (543HV0.3). The total energy of high-speed laser cladding is relatively low, accounting for 77.9% of the total energy of laser cladding, and the kinetic energy carried by high-speed particles accounts for 17.7% of the total energy of high-speed laser cladding. High-speed laser cladding can achieve high-efficiency cladding at low energy and obtain finer microstructure, more uniform composition, and higher hardness.