WC对Ni-Cr_3C_2激光熔覆层组织与性能的影响

Effect of WC on Microstructure and Propertise of Ni-Cr_3C_2 Cladding Layer

研究了WC加入量对镍基碳化铬熔覆层显微组织、横截面微观硬度及熔覆层耐磨性的影响。结果表明,WC的加入使涂层组织中出现了弥散分布的白色相,白色相由白亮色的芯部及浅白色的环形相组成,白色相从熔覆层底部至表面呈先增后减的分布规律。弥散分布的白色相使熔覆层硬度提高,当WC加入量为2wt%时,涂层平均显微硬度约1096 HV,比未加WC的平均硬度(788 HV)高308 HV。WC的加入会增加材料的脆性,影响涂层使用寿命。当WC加入量为2wt%时,熔覆层硬度与脆性增加达到最佳匹配值,对提高材料耐磨性有利。

The effects of WC on the microstructure,microhardness and wear resistance of Ni/ Cr3C2 cladding layer were studied.The experimental results show that dispersed white phase in the coatings is formed.The white phase consists of two parts,that is light white core and surrounding shallow white ring phase.The volume fraction of white phase firstly increases and then decreases from the bottom to the top of clad layer.Dispersed white phase improves the hardness of cladding layers,the average hardness of the coating with 2wt% WC is about 1096 HV,which is 308 HV higher than that without WC（788 HV）.But the WC added can increase brittleness and shorten the service life of the coating.The hardness and brittleness of the cladding layer is the best matching when the content of WC is 2wt%,which is benefit to the wear resistance of material.