摘要
本文研究了预先冷形变对Al-2.73Li合金的机械性能和断裂行为的影响。试验结果表明,预先冷形变使合金的加工硬化率和强度提高,相应损失部分塑性。预先冷形变造成不均匀分布的胞状位错结构及晶界无沉淀带加工硬化,乃是导致塑性下降的主要原因。合金的断裂方式为沿晶和穿晶混合型。预形变后时效使沿晶断裂倾向增大。最后探讨了其断裂机制。
The fracture mechanism of deformation-aged Al-Li alloy was approach-ed by investigating the influence of prior cold deformation on the precipitationkinetics as well as the behaviours of work hardening and fracture for Al-2.73 Lialloy. The experimemal results show that the work hardening rate and thestrength are increased and the ductility is decreased by prior cold defromation.The decrease in ductility is mainly due to the cell dislocation substructure distri-buted inhomogeneously and the hardening of precipitates free zones at grain bound-aries caused by prior cold deformation. The failure mode in the alloy is a mixedintergranular and transgranular fracture. The tendency of intergranular fracture isintensified through the deformation-aging. The mechanisms of intergranular failurein the alloy are different under various deformation-aging treatments
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1990年第2期A133-A139,共7页
Acta Metallurgica Sinica
关键词
AL-LI合金
断裂
预形变
时效
塑性
Al-Li alloy
deformation-aging
precipitation
strengthening
fracture
