过共晶铝硅合金的高温力学性能及显微组织演变  

High-temperature mechanical properties and microstructure evolution of hypereutectic Al-Si alloy

作　　者：刘芳[1] 于福晓[1] 张祎玲 赵大志[1] 许茜[1] 左良[3] 

机构地区：[1]东北大学材料与冶金学院,沈阳110819 [2]上海空间推进研究所,上海201112 [3]东北大学材料各向异性与织构教育部重点实验室,沈阳110819

出　　处：《中国有色金属学报》2015年第9期2358-2365,共8页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51401047);中央高校基本科研业务费项目青年教师科研启动基金资助项目(N130302002)

摘　　要：研究温度、保温时间及拉伸速度对半连续铸造Al-13.7Si合金高温力学性能和显微组织的影响。结果表明：半连续铸造Al-13.7Si合金在450℃拉伸时伸长率达到85.34%;Al-13.7Si合金表现出较高的高温塑性主要是由整个铝基体向细化的等轴晶转变引起的;Al-13.7Si合金适宜的热变形温度为450～500℃;当热变形温度高于450℃时,随着温度的升高或保温时间的延长,合金的伸长率和抗拉强度均呈下降趋势;随着拉伸速度的降低,各温度下合金的抗拉强度下降,而伸长率呈上升趋势。The high-temperature mechanical properties and microstructure of DC cast hypereutectic Al-13.7Si alloy were investigated at different temperatures, holding time and tensile velocities, The results show that the elongation of Al-13.7Si alloy is 85.43% at 450℃. Excellent ductility of the studied alloy at high temperature is due to the transformation of fine equiaxed grains in the whole Al matrix. The suitable hot deformed temperature of Al-13.7Si alloy is from 450℃ to 500℃. When the temperature of tensile is higher than 450 ℃, with increasing the temperature or prolonging the holding time, the elongation and tensile strength of the Al-13.7Si alloy decrease. With decreasing the tensile velocity, the tensile strength decreases while the elongation of the Al-13.7Si alloy increases.

关 键 词：铝硅合金 高温力学性能 组织演变 过共晶 

分 类 号：TG146.2[一般工业技术—材料科学与工程]