40Cr钢表面激光熔覆金属陶瓷复合涂层的组织和性能  

Microstructure and properties of laser clad metal ceramic composite coating on 40Cr steel

作　　者：张旭[1] 刘洪喜[1] 张晓伟[1] 姚爽[1] 李琦[1] 

机构地区：[1]昆明理工大学材料科学与工程学院,云南昆明650093

出　　处：《金属热处理》2015年第5期39-44,共6页Heat Treatment of Metals

基　　金：国家自然科学基金(61368003)

摘　　要：以WC、Ti C、Co以及Co50合金粉末为原料,在40Cr钢表面制备了WC/Co、WC/Co50以及WC-Ti C/Co50金属陶瓷复合涂层。使用X射线衍射(XRD)、金相光学显微镜(OM)、扫描电镜(SEM)和EDS能谱,对熔覆层的显微组织和物相构成进行分析。结果表明,在选择适当的激光熔覆工艺条件下,制备的WC/Co50和WC-Ti C/Co50复合涂层表面形貌良好,平整连续且无宏观裂纹。硬度测试和摩擦磨损试验表明,复合涂层具有高的硬度(涂层平均显微硬度1126.7 HV0.2以上,涂层表面硬度可达66.2 HRC以上)和良好的耐磨性,其磨损量比40Cr钢基材分别下降了54%和66%。分析认为,熔覆层硬度和耐磨性提高的原因在于熔覆层中存在大量WC、Ti C以及反应生成的W2C、Fe3W3C等碳化物增强相,且均匀分布于基体中。WC/Co,WC/Co50 and WC-TiC/Co50 composite coatings were prepared on 40Cr steel surface using WC,TiC,Co and Co50 powder as raw materials by laser cladding.The phase composition and microstructure morphology were analyzed by XRD,OM,SEM and EDS.The results show that the WC/Co50 and WC-TiC/Co50 composite coatings with good surface appearance can be reached by proper laser cladding processes.The experimental results indicate that the composite coatings have high average hardness of more than 1126.7 HV0.2 and 66.2 HRC,respectively.They also gives excellent wear resistance,which mass losses are decreased by 54％ and 66％ as that of 40Cr steel.The improvement in hardness and wear resistance is due to the presence of a great deal of WC and TiC particles and reaction generated carbide reinforced phase such as W2C and Fe3W3C and their well distribution in the composite coatings.

关 键 词：激光熔覆 陶瓷复合涂层 显微组织 硬度 耐磨性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]