Microstructure and properties of rheo-diecast Al-20Si-2Cu-1Ni-0.4Mg alloy with direct ultrasonic vibration process
The microstructure and properties of Al-20Si-2Cu-1Ni0.4Mg alloy fabricated with semi-solid rheodiecasting process were studied. A newly developed direct ultrasonic vibration process (DUV process) was used in the preparation of the semi-solid slurry of this alloy. The results show that the primary Si particles in this alloy is about 20 μm in size under DUV for 90 s in the semi-solid temperature range, compared to about 30 μm in the alloy without DUV. It is discovered that the primary Si particles distribute more homogeneously and have regular shape, but have lower volume fraction after DUV. The tensile strength at room temperature is about 310 MPa, and the tensile strength and elongation of the semi-solid die castings are increased by 34％ and 45％, respectively, compared with the traditional liquid die castings. The high-temperature tensile strength at 300℃ of this high Si aluminum alloy reaches 167 MPa, and the coefficient of thermal expansion is 17.37×10-6/℃ between 25 and 300 ℃. This indicates that this high Si content A1-Si alloy produced with the DUV process is suitable to be used in the manufacture of pistons or other heat-resistant parts.
semi-solid metals rheocasting Al-Si alloy ultrasonic vibration properties
WU Shu-sen ZHONG Gu WAN Li AN Ping MAO You-wu
State Key Lab of Materials Processing and Die &Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, China
国际会议
北京
英文
763-767
2010-09-16（万方平台首次上网日期，不代表论文的发表时间）