为了提高矿用液压立柱的使用寿命，利用激光熔覆技术在立柱用45钢材料表面制备了Fe35A合金。利用数字化测试设备对不同激光功率、扫描速度和送粉速率下制备的熔覆层进行测试，研究试样表面硬度、几何尺寸、显微组织、截面显微硬度的变化规律，得出了激光熔覆的最佳工艺参数。结果表明：在激光功率为2100 W、扫描速度为5 mm/s、送粉速率为15 g/min的最佳激光熔覆参数下制备的熔覆层的质量最佳，熔覆层的显微组织较好，晶粒细小均匀，与基体结合良好，熔覆层表面硬度可达42 HRC，熔覆层横截面显微硬度的均值为643 HV。激光熔覆层的综合力学性能明显高于基体，实现了在45钢基体表面高质量制备Fe35A合金涂层的目的。

To improve the service life of a mining hydraulic column, an Fe35A alloy layer was prepared on the surface of 45 steel material by laser cladding technology. The cladding layer, which was prepared using different laser powers, scanning speeds, and powder feeding rates, was tested using digital testing equipment to study the surface hardness, geometric size, microstructure, and sectional microhardness of the sample, and the optimal process parameters for laser cladding were obtained. Results show that under the optimal laser cladding parameters of 2100 W laser power, scanning speed of 5 mm/s, and powder feeding rate of 15 g/min, the quality of the cladding layer is the best, the microstructure of the cladding layer are good, the grain size is fine and uniform, and the fusion between the matrix structure and the cladding layer is satisfactory, the hardness of the cladding layer surface is 42 HRC, and the average microhardness of the cross-section of the cladding layer is 643 HV. The comprehensive mechanical properties of the laser cladding layer are higher than those of the matrix structure. The preparation of Fe35A alloy coating with high-quality on 45 steel substrate is realized.