脉冲电流对2091Al-Li合金超塑性及断裂行为的影响  

EFFFECT OF CURRENT PULSE ON SUPERPLASTICITY AND FRACTURE BEHAVIOUR OF 2091 Al-Li ALLOY

作　　者：刘志义[1] 崔建忠[1] 白光润[1] 

机构地区：[1]东北工学院

出　　处：《金属学报》1993年第2期A089-A092,共4页Acta Metallurgica Sinica

基　　金：国家教委博士点基金

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.

关 键 词：超塑性 断裂 铝锂合金 脉冲电流 

分 类 号：TG146.2[一般工业技术—材料科学与工程]