【摘要】 研究表明 ,Zn- 5 Al超塑性合金的应变速率敏感指数 m和超塑性变形激活能 Q值和超塑性流动粘滞系数η可采用恒载荷蠕变法进行测定。在恒载荷变形条件下 ,应变速率敏感指数 m随应变速率的增加而增大 ,超塑性流动的粘滞系数η随应变速率的增加而减小 ;超塑拉伸前对轧态试样进行保温处理时 ,由于通过回复和再结晶释放了合金中的储能 ,降低了超塑变形的动力 ,导致变形抗力增加而延伸率下降更多还原

【Abstract】 With the constant load creep method, the strain rate sensitivity exponent m, the superplastic deformation activation energy Q and the viscosity exponent η for Zn 5Al superplastic alloy was measured Experment results show that the bigger the deformation rate ε· , the bigger strain rate sensitivity exponent m, and the smaller the viscosity exponent η If the as rolled specimen is annealed before superplatic deformation, the deformation stress will become bigger and the elongation become smaller, which is because of the diminishing of the motivity of superplastic deformation due to the release of the stored energy through recovery and recrystallization更多还原