钛合金表面激光重熔镍包石墨涂层的研究

为了提高钛合金的表面耐磨性能,以镍包石墨粉末作为预涂材料,先热喷涂到Ti-6A l-4V基底表面,再采用激光技术进行重熔处理,获得了质量良好的增强涂层。通过XRD、SEM和EDS对涂层组织进行分析,结果表明:涂层的微观组织为固熔了少量Ti元素的镍基,含有大量的TiC增强相。这些TiC增强相呈现发达的枝晶状形态,是在激光重熔过程中原位反应生成的。显微维氏硬度测试表明:激光重熔涂层的硬度达到HV1200,是钛合金基底硬度的3倍。

Research of Laser Remelting Nickel-Coated Graphite Layer on Titanium Alloy Substrate

In order to improve wear resistance of titanium alloy,nickel-coated graphite powder was thermal sprayed and laser remelted on Ti-6Al-4V substrate to obtain a good reinforced layer.Microstructure of the layer was examined using XRD,SEM and EDS.The layer mainly consists of Ni with a little Ti dissolve in it as base and many TiC phases as reinforcement.TiC reinforcement is dendrite morphology in three-dimensionality.During laser remelting process,TiC reinforcements in-situ synthesized in the layer.The microhardness of the laser remelting layer measured using a Vickers hardness tester.The average microhardness of the layer is HV1200 and it is three times of titanium alloy substrate.