镁合金表面激光熔覆纳米三氧化二铝  

Laser Surface Cladding of a ZM5 Magnesium Alloy with Nano-Al_2O_3

作　　者：陈长军[1,2] 张敏[2] 常庆明[2] 张诗昌[2] 马洪岩[3] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,甘肃兰州730050 [2]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,材料与冶金学院激光加工中心,湖北武汉430081 [3]沈阳航空工业学院材料工程系,辽宁沈阳110034

出　　处：《中国激光》2008年第11期1752-1755,共4页Chinese Journal of Lasers

基　　金：有色金属合金及加工教育部重点实验室开放基金(SKL07002);湖北省教育厅科学技术研究计划优秀中青年人才项目(Q20081101)资助课题

摘　　要：镁合金由于密度小、比强度高、良好的导电和导热性而成为工业结构工程和运输工具中非常有应用前景的工程材料。但由于镁合金的耐磨性差,成为阻碍镁合金应用与汽车工业或其他工程部件中作为转动部件的一大障碍。为提高镁合金的表面耐磨性,各种表面处理技术应运而生。其中激光表面改性处理技术比较引人瞩目。为提高镁合金的表面耐磨性,采用激光熔覆纳米Al2O3颗粒的办法对ZM5镁合金进行了表面改性处理。激光改性是采用500 W脉冲Nd∶YAG熔化预置在ZM5表面的纳米三氧化二铝进行处理的。激光熔覆后,对改性层的显微结构进行了分析。同时对显微硬度与激光加工参数之间的关系以及耐磨性均进行了测试。改性层的显微硬度可以高达350 HV,而基材的显微硬度只有100 HV。激光改性处理层的耐磨性与基材相比也得到了显著的提高。Mg alloy has become promising materials for industrial structural and transport applications due to their attractive properties such as low density, high specific strength, good electrical and thermal condivity. The poor wear property is the major concern when it is subjected to motion in automotive or other engine components. To improve its wear property , many different surface engineering methods have been developed. Laser surface cladding technology is a very promising one among these methods. Nano Al2O3 particles are dispersed on the ZM5 surface by laser surface engineering to improve its wear resistance property. Laser processing is carried out with a 500 W pulsed Nd：YAG laser by melting preplaced nano-Al2 O3 particles on the surface of ZMS. Following laser processing, a detailed microstructural analysis of the surface modified layer is carried out. The microhardness of the surface layer is measured as a function of laser parameters and wear resistance property was evaluated in details. Microhardness of the surface layer is significantly improved to as high as 350 HV as compared to 100 HV of the substrate compared to the as received specimen, the wear resistance property of the laser surface modified samples is considerably improved.

关 键 词：激光技术 激光熔覆 纳米陶瓷涂层 磨损 镁合金 纳米三氧化二铝 

分 类 号：TG146.22[一般工业技术—材料科学与工程] TQ522.59[金属学及工艺—金属材料]