Influences of different Zr/Sc ratios on microstructure and mechanical properties of Al-2Si alloy  

作　　者：Qinglin Li Xiaodong Ma Binqiang Li Jiqiang Ma Xiangyu Feng Ruijie Pei Jianjun Liu 

机构地区：[1]School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China [2]State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,Lanzhou University of Technology,Lanzhou 730050,China [3]School of Materials Science and Engineering,Harbin Institute of Technology,Harbin 150001,China

出　　处：《Journal of Rare Earths》2021年第1期105-112,I0004,共9页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(51561021),China;The State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals;Lanzhou University of Technology(SKLAB02019007),China;Training Program on College Students of Gansu Province(DC2019161),China。

摘　　要：The influences of different Zr/Sc ratios on the microstructural evolution and mechanical performances of Al-2 Si alloy were investigated in this paper.The as-cast samples were characterized and analyzed by the scanning electron microscope(SEM)with an energy dispersive spectrometer(EDS)to indicate the refining effect of the different Zr/Sc ratios on theα-Al and Si phases in Al-2 Si alloy.The results indicate that theα-Al phases are refined from coarse dendritic structure to relatively fine equiaxed grains when the Zr/Sc ratio is equal to 1:1.Meanwhile,the eutectic Si phase in Al-2 Si-0.2 Zr-0.2 Sc alloy is modified from the coarse plate and needle to fine fiber and partial granular structure,and the average roundness of eutectic Si is decreased by 75%from 16 to 4.With the refinement ofα-Al phases and the modification of eutectic Si structure,the ultimate tensile strength(UTS)is improved by 53%and the elongation(EL)is increased by 64%when the Zr/Sc ratio is equal to 1:1.In addition,the UTS decreases and EL is enhanced with the increase of tensile temperature.Moreover,the fracture model of Al-2 Si-0.2 Zr-0.2 Sc alloy in250℃changes into the ductile fracture.

关 键 词：Al-Si alloy Zr/Sc ratio α-Al phases Eutectic Si Mechanical properties Rare earths 

分 类 号：TG146.21[一般工业技术—材料科学与工程]