对高速列车制动盘进行表面改性提高耐磨性是制动盘发展的趋势, 但激光熔覆镍基自熔性合金粉末后显微硬度过高, 且随熔覆层厚度增加开裂趋势越明显。为此, 研究采用微合金化技术, 探索微量合金元素对熔覆层组织及性能的影响, 通过依次添加不同含量的V、Ti、B、Si等合金元素, 优化粉末配比, 进而达到改善熔覆层目的。研究结果表明: Ti粉末晶粒细化的效果比V粉末更加明显, 最佳添加量为1%; B粉末、Si粉末优化含量分别为3.5%和4.5%。熔覆试样摩擦磨损性能测试表明: 优化配方的合金粉末熔覆层磨损率低, 耐磨性佳, 与微观组织观察、显微硬度及成形性的结果相吻合。

It is the development trend to improve the wear resistance of high speed train's brake disc by laser cladding surface modification, but the microhardness of laser cladding the Ni based self-fluxing alloy powder layer is too high, and the more laser cladding layers, the more cracks inside the laser cladding. To solve this problem, study uses micro alloying technology to explore the effects of trace alloy elements on microstructure and properties of cladding layer. The powder ratio is optimized by adding different content of V, Ti, B, Si to achieve the purpose of improving the cladding layer. The results show that the grain refinement effect of Ti powder is more obvious than that of V powder, and the best adding amount is 1%. The optimized content of B powder and Si powder are 3.5% and 4.5%. The friction and wear properties of the test samples show that the cladding layer has low wear rate and good wear resistance which are consistent with microstructure observation, microhardness and formability.