摘要
研究了脉冲电流对2091 Al-Li合金在高速超塑变形时的力学行为及断裂机制的影响。结果表明:施加脉冲电流使2091 Al-Li合金在高应变速度(10^(-2)s^(-1))时仍具有较高的应力应变速度敏感指数和超塑性能。扫描电镜观察表明,施加脉冲电流使2091 Al-Li合金的断裂机制由晶界撕裂转变成典型的超塑断裂-在粒子及晶界处形成孔洞,相互连接以至断裂。
Effects of current pulse on mechanical behaviors and fracture mechanism of
2091 Al-Li superplastically deformed at high strain rate have been investigated. Applying a
direct current pulse makes the 2091 Al-Li alloy still with high stress-strain rate sensiitivity
exponent and superplastic properties under superplastically deformed at high strain rate of
10^(-2)s^(-1). SEM observation showed that the fracture for 2091 Al-Li alloy, superplastically de-
formed at high strain rate by applying current pulse, transforms from intergranular tear to
typical superplastic failure, i. e., fracture by formation and coalescene of cavities at particles
and boundaries.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1993年第2期A089-A092,共4页
Acta Metallurgica Sinica
基金
国家教委博士点基金
关键词
超塑性
断裂
铝锂合金
脉冲电流
current pulse
superplasticity
fracture
Al-Li alloy
