铝锂合金板材的各向异性及其在旋压壳体力学性能分布中的遗传效应  

Anisotropy of Al−Li alloy plate and its heredity effect in mechanical property distribution of spun-dome

作　　者：林奔 马鹏程[4] 李昊然 邓三喜 曾广俊 唐建国 李劲风[5] 李锡武[1,2] Ben LIN;Peng-cheng MA;Hao-ran LI;San-xi DENG;Guang-jun ZENG;Jian-guo TANG;Jin-feng LI;Xi-wu LI(State Key Laboratory of Nonferrous Metals and Processes,GRINM Group Co.,Ltd.,Beijing 100088,China;General Research Institute for Nonferrous Metals,Beijing 100088,China;China Academy of Launch Vehicle Technology,Beijing 100076,China;Aerospace Research Institute of Materials Processing and Technology,Beijing 100076,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]有研科技集团有限公司有色金属材料制备加工国家重点实验室,北京100088 [2]北京有色金属研究总院,北京100088 [3]中国运载火箭技术研究院,北京100076 [4]航天材料及工艺研究所,北京100076 [5]中南大学材料科学与工程学院,长沙410083

出　　处：《Transactions of Nonferrous Metals Society of China》2023年第5期1318-1330,共13页中国有色金属学报（英文版）

摘　　要：研究厚度为20 mm的2A55铝锂合金板T6态时效(165℃,24 h)后的力学性能及晶粒组织。以20 mm厚度板材为原料,旋压制备直径为1 m的2A55铝锂合金旋压壳体,研究旋压壳体相同T6态时效后的时效析出相、晶粒组织及沿壳体轴向和周向的力学性能分布。结果表明,旋压壳体T6态时效后的析出相包括大量T1相(Al_(2)CuLi)、部分δ’相(Al_(3)Li)和θ’相(Al_(2)Cu)。T1相分布不均匀,亚晶界分布密集,但沿大角度晶界形成沿晶无沉淀带。板材同一方向力学性能基本一致,但不同方向存在各向异性,沿轧制方向强度最高而沿45°方向强度最低。旋压过程导致壳体不同位置周向和轴向与原始轧制方向的夹角变化,晶粒长宽比和织构不同。相应地,旋压壳体沿相同周向或轴向的力学性能分布存在很大差异。原始板材的各向异性在旋压壳体晶粒组织及力学性能分布方面存在遗传效应。The mechanical properties and grain structures of 2A55 Al−Li alloy plate with 20 mm in thickness after T6-aging at 165℃for 24 h were investigated.The aging precipitates,grain structures and mechanical property distribution along the circumferential and axial directions in the T6-aged spun-dome with 1 m in diameter spin-deformed through the 2A55 Al−Li alloy plate with 20 mm in thickness were studied.The precipitates in the T6-aged dome include a great number of T1(Al_(2)CuLi)precipitates and a small number of δ’(Al_(3)Li)and θ’(Al_(2)Cu)precipitates.The distribution of T1 precipitates is uneven,which is characterized by dense distribution at subgrain boundaries and the formation of precipitate-free zone(PFZ)at high angle grain boundaries.The T6-aged plate possesses almost same strength along a same direction,but there exists anisotropy with the lowest strength along 45 direction and the highest strength along the rolling direction.The T6-aged dome possesses great mechanical property discrepancy along a same circumferential direction and axial direction,which is correlated with the variation of the angle of the dome circumferential direction and axial direction to the rolling direction and the resulting different textures and grain aspect ratio at different locations.There exists a heredity effect in the grain structures and mechanical properties from the original hot-rolled plate to the subsequent spin-deformed dome.

关 键 词：铝锂合金 旋压成型 各向异性 力学性能 织构 

分 类 号：TG146.21[一般工业技术—材料科学与工程]