Zr_(55)Cu_(30)Al_(10)Ni_5非晶合金超塑性成形工艺时间

Processing time in superplastic forming for Zr_(55)Cu_(30)Al_(10)Ni_5 bulk metallic glass

通过Zr55Cu30Al10Ni5非晶合金的差示扫描量热仪(DSC)连续升温和等温退火实验,研究了影响非晶合金超塑性成形工艺时间的三种因素:退火温度,加热速率,退火加工次数.结果表明:退火温度与非晶合金孕育时间存在负指数关系,主要决定了可加工时间的长短,进而影响工艺时间的可选范围;增大加热速率可以一定程度上增大某一退火温度下的孕育时间,延长可加工时间,但是当该退火温度因增大加热速率而超出过冷液相温度区间时,孕育时间达到极大值;多次退火加工会使非晶合金的总体孕育时间出现损失,损失大小与初次退火时间成反比.合理选择退火温度、适度增大加热速率、科学安排加工顺序和过程均有助于在非晶合金超塑性成形加工中延长可加工时间,优化工艺时间,保护材料的非晶特性.

The influential factors of the processing time in the superplastic forming for Zr55Cu30Al10Ni5 bulk metallic glass by the continuous heating and isothermal annealing differential scanning calorime‐try (DSC) experiments were investigated .Three factors were investigated :the annealing tempera‐ture ,heating rate and the times of the annealing processing .The annealing temperature showed a neg‐ative exponential relationship with the incubation time of Zr 55 Cu30 Al10 Ni5 ,and mainly determined the length of the allowed processing time .Increasing the heating rate could increase the incubation time a little ,so as to extend the processing time .But when the annealing temperature went beyond the su‐percooled liquid region due to the increasing heating rate ,incubation time would achieve the maxi‐mum .Lots of annealing proceedings could make the losses of the overall incubation time ,which were related to the first annealing time .So moderately choosing the annealing temperature and the heating rate ,scientifically arranging the processing sequence can help to optimize the processing time in super‐plastic forming of bulk metallic glasses and maintaining the amorphous characteristics of materials .