等离子熔覆TiC/Fe基熔覆层显微组织及碳化物演变机理分析  

Analysis of Microstructure and Carbide Evolution Mechanism of TiC/Fe-Based Cladding Coating by Plasma Cladding

作　　者：尹燕[1] 何明明 李辉 赵奎安 刘颖波 张瑞华 YIN Yan;HE Ming-ming;LI Hui;ZHAO Kui-an;LIU Ying-bo;ZHANG Rui-hua(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China;China Iron&Steel Research Institute Group,Beijing 100081,China;Yangjiang Hardware Knife Cut Industrial Technology Research Institute,Guangdong Yangjiang 529533,China;Sichuan University of Science&Engineering,Sichuan Zigong 643000,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]中国钢研科技集团有限公司,北京100081 [3]阳江市五金刀剪产业技术研究院,广东阳江529533 [4]四川轻化工大学,四川自贡643000

出　　处：《表面技术》2023年第10期384-393,共10页Surface Technology

基　　金：国家自然科学基金(52161007);广东省科技计划项目(20170902,20180902);阳江市科技计划项目(SDZX2020009);过程装备与控制工程四川省高校重点实验室开放基金资助项目(GK202106)。

摘　　要：目的 为了提高3Cr13马氏体不锈钢的硬度和耐磨性,在其表面制备TiC/Fe基熔覆层,分析熔覆层组织的均匀性及碳化物类型,探究碳化物演变机理和对熔覆层硬度的影响规律。方法 采用等离子同步送粉熔覆,在3Cr13不锈钢基材上熔覆球形TiC/Fe基熔覆层。利用扫描电子显微镜、X射线衍射、能谱仪分析熔覆层微观形貌特征、相组成以及析出相的元素分布规律,利用显微硬度计测量熔覆层的硬度。结果 随着TiC添加量的增加,熔覆层中的Ti和C元素含量也增加,说明有部分TiC熔解。未添加TiC的熔覆层组织主要是Fe-Cr固溶体和(Fe、Cr)_(7)C_(3),TiC/Fe基熔覆层的为Fe-Cr固溶体和TiC、(Fe、Cr)_(3)C_(2)、(Fe、Cr)_(7)C_(3)。两种熔覆层中的析出相主要以(Fe、Cr)_(7)C_(3)为主,但在TiC/Fe基熔覆层中还存在其熔解后重新析出的TiC及过渡相(Fe、Cr)_(3)C_(2)。TiC添加量增加,熔覆层显微硬度也增加。结论 TiC/Fe基熔覆层中的第二相除(Fe、Cr)_(7)C_(3),还有原始TiC、析出的TiC和(Fe、Cr)_(3)C_(2)。在研究范围内,随着TiC添加量增加,熔覆层中熔解的TiC量也增加。析出的TiC.可以作为(Fe_(3)Cr_(4))C_(3)的有效形核质点,促进(Fe_(3)Cr_(4))C_(3)的形成,形成过程是(Fe、Cr)_(3)C_(2)以析出的TiC为形核核心形核长大,随后相变为更加稳定的(Fe、Cr)_(7)C_(3),在快速冷却过程中有未转变完的(Fe、Cr)_(3)C_(2)保留下来。熔覆层中的原始TiC、析出的TiC、生成的(Fe、Cr)_(7)C_(3)和(Fe、Cr)_(3)C_(2)作为硬质相提高了熔覆层的硬度。In order to improve the hardness and wear resistance of 3Cr13 martensitic stainless steel,TiC/Fe-based cladding coating was fabricated on the 3Cr13 stainless steel substrate.The homogeneity of the microstructure of the cladding coating and the type of carbides were analyzed,and the evolution mechanism of carbides and effect rule on hardness of carbides of the cladding coating were studied.Spherical TiC/Fe-based cladding coating was fabricated on the 3Cr13 martensitic stainless steel substrate by plasma cladding with coaxial powder-feed.The microstructure distribution of the cladding coating and the microscopic morphological characteristics of the precipitated phase were observed by scanning electron microscopy(SEM).The phase composition of the cladding coating was analyzed by X-ray diffraction(XRD),and the chemical composition and the distribution of elements of the precipitation phase in the cladding coating were analyzed by energy dispersive spectroscopy(EDS).With the knowledge of thermodynamics and kinetics of materials,the evolution mechanism of carbides in cladding coating was analyzed,and the hardness of the cladding coating was measured by the microhardness tester.The un-melted TiC particles appeared homogeneous distribution in the cladding coating.With the increase of TiC content,the contents of Ti and C elements increased in the cladding coating.The atomic percentage of C increased from 26.22% to 49.86%;and the atomic percentage of Ti increased from 0 to 9.56%,which indicated that some of TiC was melted.In addition,the scanning results of element distribution showed that there were cracks in the un-melted spherical TiC,which also indicated that a proportion of TiC had melted in the cladding coating.The microstructure without TiC in the cladding coating was mainly formed by Fe-Cr sosoloid and(Fe,Cr)_(7)C_(3),while the phases in the TiC/Fe-based cladding coating were mainly Fe-Cr sosoloid and TiC,(Fe,Cr)3C_(2) and(Fe,Cr)7C_(3).The precipitated phases in the two kinds of cladding coatings were mainly(Fe,Cr)

关 键 词：等离子熔覆 Fe基粉末 TIC 熔覆层 微观组织 演变机理 

分 类 号：TG174.442[金属学及工艺—金属表面处理]