激光熔敷Ti_5Si_3/NiTi金属间化合物复合材料涂层组织与耐磨性  

Microstructure and Wear-Resistant Properties of Laser Clad Ti_5Si_3/NiTi Intermetallic Composite Coating

作　　者：刘元富[1] 赵海云[1] 王华明[1] 

机构地区：[1]北京航空航天大学,北京100083

出　　处：《稀有金属材料与工程》2003年第5期367-371,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金资助项目(52101001);航空基础科学基金资助项目(01H51011);国防预研基金项目;国家高技术研究发展计划课题(2002AA331030)

摘　　要：以Ti_14Si_6Ni_(80)合金粉末为原料,利用激光熔敷技术在BT9钛合金表面制得以金属硅化物Ti_5Si_3为增强相、以金属间化合物NiTi为基体的快速凝固金属间化合物复合材料涂层,分析了该涂层的显微组织,在室温干滑动磨损条件下测试了其耐磨性。研究结果表明,涂层硬度高、组织致密、与基材之间为完全冶金结合,在干滑动磨损试验条件下具有较好的耐磨性。涂层具有优异耐磨性的主要原因是作为耐磨增强相的金属硅化物Ti5Si3具有高硬高耐磨的特性,在涂层中起到了抗磨骨干作用,同时作为涂层基体的金属间化合物NiTi由于具有极强的原子结合键及应力诱发马氏体相变特性,本身具有优异的耐磨性,在摩擦过程中对耐磨增强相Ti5Si3起到了强力支撑作用。A novel rapidly solidified Ti5Si3/NiTi intermetallic composite coating was fabricated on substrate of a titanium alloy BT9 by laser cladding using the Ni-14Ti-6Si alloy powders. Microstructure of the coating was characterized by OM, SEM, XRD and EDS. Wear resistance of the coating was tested under dry sliding wear condition at room temperature. The results indicate that the laser clad intermetallic composite coating has a homogeneous rapidly solidified microstructure consisting of Ti5Si3 primary particles uniformly distributed in the NiTi matrix,and is metallurgically bonded to the titanium substrate. The laser clad intermetallic composite coating has high hardness and excellent wear resistance under dry sliding wear test condition. The excellent wear resistance of the laser clad Ti5Si3/NiTi intermetallic composite coating is attributed to the high hardness and strong atomic bonding of the reinforcing Ti5Si3 phase and to the strain-induced martensite transformation of the NiTi intermetallic matrix.

关 键 词：激光熔敷 金属间化合物复合材料 涂层 显微组织 耐磨性 

分 类 号：TG174.44[金属学及工艺—金属表面处理]