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针对超高速电梯安全钳楔块耐高温磨损性差的问题,以FeV粉、石墨粉和Ni粉为原料,在楔块摩擦面进行了激光熔覆原位生成VC-Fe_3C/Fe-Ni复合涂层的实验,分析了不同粉末质量配比、不同工艺参数下熔覆层的组织演变规律,测试了熔覆层的硬度、高温耐磨损性和冲击韧性等力学性能。研究表明:通过原位反应,可获得由VC、Fe-Ni固溶体和Fe_3C组成的复合涂层;VC的含量随石墨含量的增加而增加;在较低的扫描速度下,VC颗粒呈球状或胞状,弥散分布在Fe-Ni固溶体上。当扫描速度较高时,VC呈菊花状、枝晶状和块状,主要分布在晶界上;当FeV粉、石墨粉和Ni粉的质量比是8∶3∶8时,熔覆层搭接时不产生裂纹,复合涂层平均维氏硬度5.9GPa,VC-Fe_3C/Fe-Ni涂层高温磨损量为Ni60激光熔覆层的25%,为45钢的9.7%,VC-Fe_3C/Fe-Ni涂层冲击韧度值比Ni60激光熔覆层提高37.6%。将该工艺应用于电梯安全钳等零件的强化领域,将大大提高电梯零件的耐磨性和使用寿命。
Aiming at the problem that the wedge of ultra-high speed elevator safety wiper is poor in high temperature wear resistance, the VC-Fe3C / Fe-Ni composite coating is prepared by laser cladding on the wedge friction surface using FeV powder, graphite powder and Ni powder as raw materials , The microstructure evolution of the cladding layer under different powder quality ratios and different process parameters was analyzed. The mechanical properties such as hardness, high temperature wear resistance and impact toughness were tested. The results show that the composite coating composed of VC, Fe-Ni solid solution and Fe_3C can be obtained by in-situ reaction. The content of VC increases with the increase of graphite content. At lower scanning speed, VC particles are spherical or cellular , Dispersed in the Fe-Ni solid solution. When the scanning speed is high, VC is daisy, dendrites and massive, mainly in the grain boundary; when the mass ratio of FeV powder, graphite powder and Ni powder is 8: 3: 8, the cladding layer The average Vickers hardness of the composite coating was 5.9 GPa. The wear amount of the VC-Fe 3 C / Fe-Ni coating was 25% of that of the Ni60 laser cladding layer, 9.7% of that of the 45 steel, and the VC-Fe 3 C / Fe The impact toughness of Ni coating is 37.6% higher than Ni60 laser cladding layer. The process used in the elevator safety gear and other parts of the area of strengthening, will greatly enhance the wear resistance and service life of the elevator parts.