Strength and structure variation of 2195 Al-Li alloy caused by different deformation processes of hot extrusion and cold-rolling  

2195铝锂合金力学性能及组织与热挤压及冷轧变形过程的相关性

作　　者：Yun-long MA Jin-feng LI Run-zhe ZHANG Jian-guo TANG Cheng HUANG Hong-ying LI Zi-qiao ZHENG 马云龙;李劲风;章润喆;唐建国;黄诚;李红英;郑子樵(中南大学材料科学与工程学院,长沙410083;北京宇航系统工程研究所,北京100076;中南大学轻合金研究院,长沙410083;中南大学教育部有色金属材料与工程重点实验室,长沙410083)

机构地区：[1]School of Materials Science and Engineering,Central South University,Changsha 410083,China [2]Beijing Institute of Astronautical Systems Engineering,Beijing 100076,China [3]Light Alloy Research Institute,Central South University,Changsha 410083,China [4]Key Laboratory of Nonferrous Materials Science and Engineering of Ministry of Education,Central South University,Changsha 410083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第4期835-849,共15页中国有色金属学报（英文版）

基　　金：Project(2013AA032401)supported by the National High Technology Research and Development Program of China。

摘　　要：2195 Al-Li alloy was deformed through extrusion followed by cold-rolling.The textures of the extruded plate and cold-rolled sheet after solutionization were investigated.The longitudinal strength and precipitates after T8 aging were measured and observed,respectively.Compared to those in the sheet,T1(Al2 Cu Li)precipitates in the extruded plate after T8 aging are non-uniform,and their incubation time is shorter.The extruded plate after solutionization is not recrystallized and contains 55.28%deformation textures of Brass and S.In the cold-rolled sheet after solutionization,massive recrystallization occurs and S component disappears.Due to the higher fraction of Brass and S textures with higher Schmid factor and lower equivalent sliding system number,the extruded plate possesses an yield strength not higher or even lower,but a tensile strength higher,than the cold-rolled sheet after solutionization.In addition,during the aging after pre-stretch,these textures promote T1 precipitation on preferred sliding planes of cold-rolled sheet and cause its higher yield strength and tensile strength after T8 aging.采用挤压及后续冷轧变形制备2195铝锂合金板材,研究固溶处理后挤压板材及冷轧薄板的织构以及T8时效后的析出相及纵向强度。结果表明,挤压板T8时效时T1(Al2Cu Li)相分布不均匀而且孕育期较短。挤压板固溶处理后未发生再结晶,变形织构Brass和S体积分数达55.28%。而冷轧薄板固溶处理后发生严重再结晶,且S变形织构消失。由于固溶态挤压板Brass和S织构分数高,其Schmid因子大,等效滑移系数量少,因而其屈服强度不高甚至低于固溶态冷轧板,但抗拉强度则明显较高。另外,在预变形后的时效过程中,这些变形织构促进T1相在优先滑移面析出,从而导致时效态挤压板屈服强度及抗拉强度均高于时效后的冷轧薄板。

关 键 词：Al-Li alloy COLD-ROLLING EXTRUSION TEXTURE PRECIPITATE STRENGTH 

分 类 号：TG146.21[一般工业技术—材料科学与工程]