Effect of solution treatment on microstructure and mechanical properties of as-cast Al-12Si-4Cu-2Ni-0.8Mg-0.2Gd alloy  

作　　者：Yu-dong Sui Ye-hua Jiang Qu-dong Wang 

机构地区：[1]School of Materials Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China [2]National Engineering Research Center of Light Alloys Net Forming and State Key Laboratory of Metal Matrix Composite,Shanghai Jiao Tong University,Shanghai 200240,China

出　　处：《China Foundry》2022年第3期238-244,共7页中国铸造（英文版）

基　　金：the National Natural Science Foundation of China(No.U1902220);Yunnan Fundamental Research Projects(No.202101BE070001-041).

摘　　要：Effect of solution treatment on microstructure and mechanical properties of Al-12Si-4Cu-2Ni-0.8Mg-0.2Gd alloy was investigated.Results show the Si particles become stable and more intermetallic compounds dissolve in the matrix after solution treatment at 500℃for 2 h followed by 540℃for 3 h(T4).The skeleton-like Al_(3)CuNi develops into two parts in the T4 alloy:one is Al_(3)CuNi which has the framework shape;the other is intermetallics including the Al_(3)CuNi(size:5-10μm)and AlSiCuNiGd phases(size:≤5μm)with complex structure.Adding 0.2%Gd can improve the mechanical properties of the alloys after two-step solution treatment(500℃/2 h followed by 540℃/3 h),the hardness of the alloy increases from 130.9 HV to 135.8 HV compared with the alloy with one-step solution treatment(500℃/2 h),the engineering strength increases from 335.45 MPa to 352.03 MPa and the fracture engineering strain increases from 1.44%to 1.67%.

关 键 词：Al-Si-Cu-Ni-Mg alloy Gd element solution treatment microstructure mechanical properties 

分 类 号：TG146.21[一般工业技术—材料科学与工程]