稀土元素La、Ce对Al-3Si-0.4Cu-1.0Fe压铸铝合金微观组织、力学性能及热导率的影响  

Effect of Rare Earth La and Ce on the Microstructure,Mechanical Properties,and Thermal Conductivity of Al-3Si-0.4Cu-1.0Fe Die Casting Aluminum Alloy

作　　者：甘培原 韦德仕 韦世强 秦文忠 彭健飞 曾杰 GAN Pei-yuan;WEI De-shi;WEI Shi-qang;QIN Wen-zhong;PENG Jian-fei;ZENG Jie(Chinalco Guangxi Nonferrous Rare Earth Development Co.,Ltd.,Nanning 530024,China;Guangxi Guorui Rare Scandium New Material Technology Co.,Ltd.,Chongzuo 532100,China;School of Metallurgy and Environment,Central South University,Changsha 410083,China)

机构地区：[1]中铝广西有色稀土开发有限公司,广西南宁530024 [2]广西国瑞稀钪新材料科技有限公司,广西崇左532100 [3]中南大学冶金与环境学院,湖南长沙410083

出　　处：《稀有金属与硬质合金》2023年第5期50-56,72,共8页Rare Metals and Cemented Carbides

基　　金：广西创新驱动发展专项(桂科AA17204036);广西重点研发计划项目(2021AB17090)。

摘　　要：为提高Al-Si系压铸铝合金的热导率与力学性能,利用金相显微镜、扫描电镜、能谱仪、万能电子拉伸试验机与激光热导仪等设备研究了稀土元素La、Ce对压铸铝合金Al-3Si-0.4Cu-1.0Fe微观组织、热导率及力学性能的影响。结果表明,稀土元素La、Ce使合金晶粒细化,α-Al晶粒由枝晶转变为胞状形态,降低了平均二次枝晶臂间距;也能变质合金中的共晶Si相,使其呈细小纤维状形态均匀分布。当稀土元素La、Ce添加量均为0.1%时,合金的热导率、抗拉强度、断后伸长率分别达到167.62 W/(m·K)、201.0 MPa、14.56%,较未添加稀土元素的合金分别提高了11.19%、27.38%和246.67%。In order to improve the thermal conductivity and mechanical properties of Al-Si based die casting aluminum alloys,the effects of La and Ce on microstructure,thermal conductivity and mechanical properties of Al-3Si-0.4Cu-1.0Fe die casting aluminum alloy were investigated using metallographic microscope,SEM,EDS,universal electronic tensile testing machine,and laser conductometer.The results indicate that the rare earth elements of La and Ce refine the alloy grains,transformingα-Al grains from dendrite to cellular morphology,and reducing the average secondary dentritic arm spacing.Meanwhile,the two elements also modify the eutectic Si phase to result in a uniform distribution of fine fibrous morphology.When the added contents of La and Ce are both 0.1%,the thermal conductivity,tensile strength and elongation after fracture are 167.62 W/(m·K),201.0 MPa,and 14.56%,respectively.Compared with the sample without rare earth elements,these values are increased by 11.19%,27.38%,and 246.67%.

关 键 词：压铸铝合金 La CE 微观组织 二次枝晶臂间距 热导率 力学性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程]