双层WC颗粒增强铁基体复合熔覆层的组织和性能研究  

Research on Mirostructure and Property of Double WC Particle Reinforced Fe-based Composite Claddings

作　　者：叶诚[1] 杜晓东[1] 李连颖[1] 杨皓宇[1] 宋自力[1] 

机构地区：[1]合肥工业大学材料科学与工程学院,合肥230009

出　　处：《表面技术》2011年第3期22-25,35,共5页Surface Technology

基　　金：科技部创新基金(09C26213404170);安徽省教育厅自然科学重点项目(KJ2009A094)

摘　　要：采用氩弧熔覆(GTAW)技术在45号钢表面制备了双层WC颗粒增强铁基体复合涂层,通过SEM,XRD和EDS分析了熔覆层的显微组织和相组成,并测试了熔覆层的显微硬度。结果表明:双层复合熔覆层内未见明显裂纹、夹杂等缺陷,与基体呈冶金结合;熔覆层的显微组织由未熔WC颗粒、灰色等轴状初晶和鱼骨状共晶碳化物组成;复合熔覆层的显微硬度由表及里先增加后降低,在近表面出现峰值,高达1 600HV0.2,约为基体硬度的5倍。Double WC particle reinforced Fe based composite coatings were prepared on a substrate of 45 steel u sing GTAW cladding technique. The microstructure and phase constitution of cladding were analyzed by scanning elec-tron microscope （SEM）, X ray diffraction （XRD）, energy dispersive spectrometer （EDS） and its microhardness was tested. The experimental results demonstrate that the double composite claddings are free of cracks and inclusions and the interface between the coating and substacte has excellent bonding and is free of cracks and inclusions. The mircrostructure is consisted of undissolved WC, primary dendrite and fishbone-like interdendritic carbide. The microhardness of the double composite claddings increases first and then decreases from surface to substrate, profile shows a gradient distribution, The microhardness is about 5 times higher than that of 45 steel and the maximum microhardness can reach 1 600HV0.2 at near-surface.

关 键 词：WC 氩弧熔覆 铁基体熔覆层 组织 硬度 

分 类 号：TG174.442[金属学及工艺—金属表面处理]