提高1420铝锂合金板材超塑性的方法  

Methods of Improving superplasticity for 1420 Al-Li Alloy Sheets

作　　者：张新明[1] 雷钊[1] 叶凌英[1] 赵莎[1] 

机构地区：[1]中南大学材料科学与工程学院,教育部有色金属材料科学与工程重点实验室,湖南长沙410083

出　　处：《热加工工艺》2012年第23期9-12,共4页Hot Working Technology

基　　金：国际科技合作重点资助项目(2008DFR50260)

摘　　要：采用一种新型形变热处理方法在工业条件下制备了1420铝锂合金超塑性板材,通过高温拉伸、金相、扫描电镜观察等检测分析手段研究了该板材的超塑性能。组织观察表明,该板材具有扁平状的晶粒组织和较强的形变织构;当试样在475～525℃和5×10-4～1×10-3s-1条件拉伸时,最高伸长率为480%。通过改变变形温度和应变速率的两阶段拉伸和变形前再结晶退火处理,最高超塑性伸长率分别提高到600%和960%。Superplastic 1420 A1-Li alloy sheets were prepared by a novel thermo-mechanical processing under industrial conditions, and the superplasticity of the sheet was investigated by high temperature tensile test, optical microscopy and scanning electron microscopy. The microstructure observation shows that the sheets have elongated grains and strong deformed texture. When the samples are tested by uniaxial tensile at 475-525℃ and strain rates range of 5×10-4 -1×10-3 s-1, the maximum elongation is 480%. The maximum elongation increases to 600% and 960%, respectively, by two stage tensile of changing deformation temperature and strain rates, and recrystallized treatment before deformation.

关 键 词：1420铝锂合金 晶粒细化 形变热处理 超塑性 

分 类 号：TG166.3[金属学及工艺—热处理]