混合稀土(Pr+Ce)变质处理ZL105铝合金摩擦磨损性能研究  

Study on the Friction and Wear Properties of ZL105 Aluminum Alloy Modified by Mixed Rare Earth(Pr+Ce)

作　　者：陈晖[1] 周烨[1] 曾敏[1] 杜丘美 胡文华 CHEN Hui;ZHOU Ye;ZENG Min;DU Qiu-mei;HU Wen-hua(School of New Energy Vehicles,Nanchang Institute of Science and Technology,Nanchang 330108,China)

机构地区：[1]南昌工学院新能源车辆学院,江西南昌330108

出　　处：《稀有金属与硬质合金》2022年第4期71-76,82,共7页Rare Metals and Cemented Carbides

基　　金：2019年江西省教育厅科学技术一般项目(GJ191102);2020江西省教育厅科技项目重点项目(GJ202501);2021江西省教育厅科技项目(GJ212523)。

摘　　要：利用光学显微镜、扫描电子显微镜和销盘式摩擦磨损试验机研究了混合稀土(Pr+Ce)对ZL105铝合金微观组织和耐磨性能的影响。结果表明:添加适量的混合稀土(Pr+Ce)可有效细化α-Al晶粒和共晶Si相,当稀土含量为0.50%时,细化效果最佳,α-Al晶粒变得细小而圆整,αA1枝晶晶界也变清晰;变质后共晶Si相由针片状、板块状转化为短棒状、颗粒状。未变质ZL105铝合金的硬度值为70.9HV,而添加0.50%混合稀土的变质合金硬度值达到最高,为88.3HV,与未变质合金相比提升了24.54%。未变质处理合金的耐磨性能较差,其磨损量和摩擦系数分别为0.1927g和0.598,而添加0.50%混合稀土后合金的磨损量和摩擦系数分别为0.1220g和0.520,磨损量减少了0.0707g,摩擦系数降低了13.04%。ZL105铝合金的磨损机制主要为剥层磨损,且磨屑尺寸粗大;而当添加0.50%稀土后,变质合金的磨损机制主要为磨粒磨损,且磨屑以细颗粒和粉末状为主。Effects of mixed rare earth(Pr+Ce)on the microstructure and wear resistance of ZL105 aluminum alloy were studied by using optical microscope,scanning electron microscope and pin-disc friction and wear tester.The results show that the addition of an appropriate amount of mixed rare earth(Pr+Ce)can effectively refine theα-Al crystal grains and the eutectic Si phase.When the rare earth content is 0.50%,the refining effect is the best and theα-Al crystal grains become fine,small,and rounded.Also,theα-Al dendrite grain boundary becomes clear.The eutectic Si phase changes from needle-like and plate-like to short rod-like and granular.The hardness of the unmodified ZL105 aluminum alloy is 70.9 HV while the hardness of the modified alloy with 0.50%mixed rare earth reaches the highest of 88.3HV,which is 24.54%higher than that of the unmodified alloy.The unmodified alloy has poor wear resistance,with wear loss and friction coefficient of o.1927 g and 0.598,respectively,while the wear loss and friction coefficient of the alloy with 0.50%rare earth are 0.1220 g and 0.520,respectively,with wear loss decreasing by 0.0707 g and friction coefficient decreasing by 13.04%.The wear mechanism of ZL105 aluminum alloy is mainly delamination wear,and the size of wear debris is coarse.When 0.50%rare earth is added,the wear mechanism of modified alloy is mainly abrasive wear,and the wear debris mainly consists of fine particles andpowder.

关 键 词：ZL105铝合金 混合稀土 (Pr+Ce)变质 微观组织 摩擦磨损性能 磨损机制 

分 类 号：TG146[一般工业技术—材料科学与工程]