【摘要】 采用扫描电镜（SEM）、能谱分析仪（EDS）、X射线衍射仪（XRD）、显微硬度仪及滑动磨损试验,研究了1%纳米CeO₂（质量分数）对低碳钢表面激光熔覆Fe/Cr₃C₂复合涂层的组织结构和耐磨性能的影响。结果表明,Fe+Cr₃C₂+1%CeO₂复合涂层的主要组成相是α-Fe、γ-Fe、Cr₃C₂、Cr₂₃C₆及Cr₇C₃等化合物相;加入1%纳米CeO₂后,复合涂层组织明显细化,未熔Cr₃C₂数量显著减少,初生碳化物由粗大杆状向块状转变,数量增加,分布均匀,有效抑制和消除了裂纹的形成;复合涂层硬度和耐磨性能显著提高,Fe+30%Cr₃C₂+1%CeO₂涂层截面显微硬度提高105HV,增幅达到15.4%,且涂层沿深度方向硬度分布均匀性得到明显改善。更多还原

【Abstract】 The effects of 1%nano-CeO₂ doping to the organizational structure and wear resistance of Fe/Cr₃C₂ composite coatings formed by using laser cladding on low-carbon steel surface has been researched in this paper with the aid of SEM,EDS,XRD,micro-hardness tester and sliding wearing test.Experimental results demonstrated that compound phases such asα-Fe,γ-Fe,Cr₃C₂,Cr₂₃C₆,Cr₇C₃,etc.are the main constituent phases of Fe+Cr₃C₂+1%CeO₂composite coatings.Composite coatings’microstructures were refined obviously after adding 1%nano-CeO₂,and the quantities of non-cladding Cr₃C₂reduced significantly,as well as the primary carbides transformed from coarse rod to block with risen quantity and uniform distribution,which effectively restrained and eliminated crack formation.The hardnesses and wear resistances of the Fe+Cr₃C₂+1%CeO₂composite coatings were improved significantly,and in particular,the cross-sectional micro-hardness of Fe+30%Cr₃C₂+1%CeO₂coating was 105HV higher than that of Fe+30%Cr₃C₂ coating（increased by 15.4%）.Meanwhile,the hardness distribution homogeneities of the doped coatings along depth direction gets improved apparently.更多还原