3种高强铝合金的低温拉伸力学性能研究  

Tensile Properties of Three Kinds of Aluminum Alloys at Low Temperature

作　　者：刘瑛[1] 张新明[1] 李慧中[1] 刘波[1] 高慧[1] 李惠杰[1] 

机构地区：[1]中南大学材料学院,湖南长沙410083

出　　处：《金属热处理》2007年第1期53-56,共4页Heat Treatment of Metals

基　　金：博士点基金项目(2004053304);国家"973"重点基础发展研究规划项目(2005CB623700)

摘　　要：利用拉伸测试、扫描电镜与透射电镜等手段,研究了2519-T87、2219-T81以及7039-T6三种铝合金板材的拉伸力学性能。结果表明,当变形温度由室温293 K降至77 K时,3种合金的屈服强度与抗拉强度均有所提高,其中抗拉强度分别提高23.1%、12.0%及6.2%。同时3种合金的伸长率随着温度降低有所提高。由于低温变形过程中平面滑移受抑制,加工硬化指数增加,变形均匀性增强,导致材料的强度增加,塑性有所提高。Tensile properties of 2519-T87,2219-T81 and 7039-T6 aluminum alloy at low temperature were investigated by means of tensile properties test, scanning electron microscopy （ SEM ） and transmission electron microscopy （ TEM ）. The results show that the ultimate tensile strength （UTS） and yield strength （YS） of all the specimens increase with the decrease of temperature from 293 K to 77 K,the UTS of the 3 alloys increases by 23.1% ,12% and 6. 2% respectively. The elongation of those specimens deformed at 77 K increases by small percent. Deformed at low temperature,planar slip is inactivated and the deformation homogeneity and strain hardening exponent are both strengthened.

关 键 词：铝合金 拉伸性能 位错 

分 类 号：TG146[一般工业技术—材料科学与工程]