反应钎涂碳化物/铁基自熔合金复合涂层及组织形成机理  

Reactive braze coating carbide/Fe-based self-fluxing alloy composite coating and its microstructure forming mechanism

作　　者：裴新军[1] 张建纲[1] 黄继华[1] 魏世忠 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]河南省耐磨材料工程技术研究中心,洛阳471003

出　　处：《粉末冶金技术》2006年第1期8-12,共5页Powder Metallurgy Technology

基　　金：河南省杰出人才创新基金资助项目(0421001000)

摘　　要：利用工业原料纯铁粉、硅粉、钛铁粉、硼铁粉、铬铁粉、胶体石墨以及镍粉,真空条件下通过反应钎涂于1200℃在低碳钢基体上制备了白色、表面光滑、平整且与基体为冶金结合的碳化物/铁基合金复合涂层。采用扫描电子显微镜、能谱仪、X射线衍射仪及硬度计,研究了涂层的相组成、组织结构和成分分布。结果表明:涂层为复合结构,不存在分层现象,其组织由粘结相γ-Fe固溶体,以及-αFe(马氏体)(、Fe,Cr)7C3相和TiC相构成。涂层中通过反应原位合成的(Fe,Cr)7C3和TiC形状不同,(Fe,Cr)7C3的形状大部分为针状,而TiC形状为颗粒状,且主要分布在先前的钛铁粉颗粒轮廓之内。该复合涂层表面硬度高达73.9HR30N以上。In this paper, white carbide/Fe based composite coatings with bright and smooth surface bonded with a metallurgical bond to a mild steel substrate were synthesized by reactive braze coating （RBC） of the mixed carbon, iron, silicon, ferrochromium, ferrotitanium and nickel powder in vacuum braze furnace. The phases, microstructure and composition of the coating have been studied by means of scanning electron microscopy （SEM）, energy dispersive spectrum （EDS）, X- ray diffraction （XRD） and hardness testing. The results show that there is only a layer of composite coating, and the microstructure of the coating consists of the bonding phase of γ-Fe based solid solution, α-Fe（martensite）,（Fe, Cr）7C3 and TiC. The shape of TiC and （Fe, Cr）TC3 in situ synthesized during braze coating process is different. （Fe, Cr）TC3 is in the shape of needle and TiC mainly distributed within the former powder of ferrotitanium is granular. Surface hardness of the coaling is high up to 65HRC.

关 键 词：反应钎涂 碳化物 复合涂层 铁摹自熔合金 显微组织 

分 类 号：TG174.442[金属学及工艺—金属表面处理] TG174.44[金属学及工艺—金属学]