Preparation of a novel ultra-high strength Al–Si–Cu–Ni alloy at room/elevated temperature by squeeze casting combined with a new heat treatment process  

作　　者：Shulin Lü Shilong Li Zhaoxiang Yan Shusen Wu Jianyu Li Xiaoyuan Ji 

机构地区：[1]State Key Lab of Materials Processing and Die&Mould Technology,School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan,430074,PR China

出　　处：《Progress in Natural Science:Materials International》2024年第4期690-701,共12页自然科学进展·国际材料(英文版)

基　　金：funded by the Project 52205364 supported by National Natural Science Foundation of China

摘　　要：In this paper,the microstructure evolution and properties of squeeze-cast Al–8Si-1.5Cu–1Ni-0.5Mg-0.5Mn-0.2V-0.2Ti-0.2Zr alloy(hereafter,Al–Si–Cu–Ni alloy for short)were investigated under various solution processes,evaluating the mechanical properties at room and elevated temperatures for both as-cast and T6-treated states.The results showed that following the optimal two-stage solution(i.e.,solution at 510°C for 6 h+solution at 530°C for 8 h)and subsequent aging at 190°C for 10 h,referred to as the S530-T6 treatment,the Al–Si–Cu–Ni alloy exhibited excellent room/high temperature performance.The ultimate tensile strength(UTS),yield strength(YS)and elongation of the alloy at room temperature were 410 MPa,368 MPa and 1.5%,and the UTS,YS and elongation of alloy at 300°C were 177 MPa,170 MPa and 6%,respectively.The increase in strength at room temperature is mainly attributed to the spheroidization of eutectic silicon and the precipitate strengthening aroused from uniformly dispersed nano-sized Q-Al_(4)Cu_(2)Mg_(8)Si_(7),σ-Al_(5)Cu_(6)Mg_(2)andθ'-Al_(2)Cu phases,while the increase in strength at high temperature is due to the formation of heat-resistant Ni-rich phases and the improvement of the micromorphology of high melting point intermetallic compounds.

关 键 词：Al-Si-Cu-Ni alloy Heat treatment Squeeze casting Ultra-high strength Microstructure 

分 类 号：TG292[金属学及工艺—铸造] TG156