热压参数对TA15合金流动应力及显微组织的影响

Influence of hot compression parameters on flow stress and microstructure of TA15 alloy

在α＋β两相区和β单相区对TA15合金进行恒应变速率等温压缩试验，实测得到了一组流动应力应变曲线，并对流动应力及压缩后的显微组织变化规律进行分析。结果表明：应变速率对TA15合金的流动应力有显著影响，变形温度对流动应力的影响程度与应变速率大小密切相关；较低温度快速压缩时易得到均匀细小等轴α相组织，慢速压缩时组织有一定的粗化。较佳等温压缩温度为900℃～980℃，应变速率可根据锻件成形、组织性能及生产率的需要在一定范围内选取，宜采用适当大的应变速率。

The test of the isothermal compression with constant strain rate of TA15 alloy has been studied at the α＋β phase region and β phase region in this paper. The stress-strain curves of it have obtained and changing laws of the flow stress and microstructure have been discussed. The results show that the strain rate obviously affects the flow stress of TA15. The extent of the effect of deformation temperature on flow stress is related to the measure of strain rate. The uniform, fine and equiaxed u phase structure is achieved at lower temperature and faster strain rate. But the structure was coarsened definitely at slow strain rate. The optimum isothermal compression temperature is between 980℃ and 900℃, the strain rate may be selected within the constant range according to the need of forging forming, structure properties and productivity. Under good forming condition of forgings, strain rate may be appropriately raised.