激光熔敷镍石墨烯立方氮化硼涂层的耐磨性能

Tribological properties of laser cladded Gr-CBN-Ni coating

在AISI 4140基体上采用预置材料激光熔敷的方法制备了镍石墨烯立方氮化硼(Ni-GrapheneCBN)复合材料涂层。X射线衍射(XRD)和Raman测试证明了石墨烯和CBN存在于所制备的涂层材料中。扫描电镜(SEM)图片给出了所制备的复合材料涂层的表面和断面形貌。进行了复合材料涂层的纳米机械性能和耐磨性的测试。测试结果表明:随着CBN含量的增加,复合涂层的硬度及弹性模量相应提高,分别由4.3GPa提高到6.2GPa和101GPa提高到140GPa;同时其耐磨性也有明显改善,6%CBN含量的涂层摩擦系数由基体材料的0.2降低到0.15,最大磨损量降到基体磨损量的一半。

Graphene（Gr）-CBN-Ni composite coating layer was fabricated by laser cladding through pre-set the mixture of nickel,graphene and CBN powders on AISI 4140 steel substrate.Microstructures and surface and sectional surface morphologies were studied using scanning electron microscopy（SEM）,XRD and Raman spectroscopy.It is proved by X-ray diffraction（XRD）patterns and Raman spectra that graphene and CBN exist in the laser cladded coating layer.The nanomechanical properties and wear and friction properties were studied.The test results show that as the CBN content increases,the coating layer has better properties.The hardness and modulus of coating layer were significantly enhanced with the CBN content increasing.The average hardness were 4.3GPa and 6.2GPa,the average modulus were 101 GPa and 140 GPa,respectively.For 6% CBN content coating,the friction coefficient reduced to 0.15,while the substrate＇s was 0.2,and the wear loss was only the half amount compared with that of substrate＇s.