稀土元素La变质Al-5Si合金耐磨性能研究  

Study on wear resistance of Al-5Si alloy modified by rare earth element La

作　　者：张波 徐冬 张书维 宋宝成 Zhang Bo;Xu Dong;Zhang Shuwei;Song Baocheng(School of Mechanical Engineering,Jiangsu College of Safety Technology,Xuzhou 221000,China)

机构地区：[1]江苏安全技术职业学院机械工程学院,江苏徐州221000

出　　处：《轻金属》2022年第9期48-52,共5页Light Metals

基　　金：江苏省高等学校自然科学研究项目资助(19KJD440002)。

摘　　要：利用光学显微镜、扫描电子显微镜、维氏硬度计和销盘式摩擦磨损试验机等手段,研究了稀土La变质处理对Al-5Si合金微观组织、维氏硬度和摩擦磨损性能的影响。结果表明:添加了质量分数0.5%La之后,α-Al晶粒和共晶Si相均得到明显细化,大部分α-Al晶粒边界变得圆整,并且共晶Si相呈现弥散分布的细小颗粒状。Al-5Si合金基体的硬度和磨损量分别为68.71 HV和0.1644 g,添加质量分数0.5%La的合金的硬度和磨损量均达到最佳,分别为91.23 HV和0.1191 g,稀土La的加入有效增强了合金的抗磨损性能。不同稀土添加量的合金磨损机制也各不相同,未变质处理的Al-5Si合金主要为剥层磨损,而添加质量分数0.25%La和0.5%La之后,合金的磨损机制转变为磨粒磨损和粘着磨损。The effects of rare earth La modification on microstructure,Vickers hardness and friction and wear properties of Al-5Si alloy were studied by means of optical microscope,scanning electron microscope,Vickers hardness tester and pin-disk friction and wear tester.The results show that theα-Al grain and eutectic Si phase are obviously refined after adding 0.5%rare earth La,most ofα-Al grain boundaries become round,and eutectic Si phase presents fine granular distribution.The hardness and wear extent of Al-5Si alloy matrix are 68.71 HV and 0.1644 g,respectively.The hardness and wear extent of the alloy with 0.5%La are the best,which are 91.23 HV and 0.1191 g,respectively.The addition of rare earth La can improve the wear resistance of Al-5Si alloy effectively.The wear mechanism of alloys with different rare earth additions is also different.The unmodified Al-5Si alloy is mainly characterized by delamination wear,but with the addition of 0.25%La and 0.5%La,the wear mechanism of the alloy changes to abrasive wear and adhesion wear.

关 键 词：La变质 Al-5Si合金 磨损机制 摩擦磨损性能 

分 类 号：TF822[冶金工程—有色金属冶金] TG14[一般工业技术—材料科学与工程] TB31[金属学及工艺—金属材料]