摘要
研究了预冷变形和分级时效处理对2091型Al-Li合金显微组织和力学性能的影响。结果表明,固溶后8％预冷变形随后170℃,6h+190℃,4h双级时效可以使合金获得良好的强塑性配合。合金中主要强化相δ′(Al_3Li)适宜的粒度,第二强化相S′(Al_2CuMg)沿冷加工所造成的位错亚结构分散沉淀,晶界上平密相析出量的减少以及Δδ′无沉淀析出带(PFZ)的窄化,是这种合金强塑性改善的主要原因。
The effect of cold rolling prior to aging and two-step aging treatment
on the microstructure and mechanical properties of 2091 Al-Li alloy has been inves-
tigated. The superior strength-ductility of the alloy may be matched by the treat-
ment of 8% prior cold rolling and subsequently 170℃, 6h+190℃, 4 h double aging
after solid solutioning. The principal reasons for improving the strength-ducti-
lity of the alloy are the suitable particle size of σ′ (Al_3Li), the dispersal precipita-
tion of second strengthening phase S′ (Al_2CuMg) along dislocation substructures in-
troduced by cold rolling, the decrease of equilibrium phase precipitated and the
narrowing σ′ precipitate free zone at grain boundary.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1991年第2期A130-A136,共7页
Acta Metallurgica Sinica
基金
中国有色金属工业总公司基金
关键词
AL-LI合金
形变
热处理
显微组织
Al-Li alloy
thermo-mechanical treatment
microstructure
mechanical properties
