粗片层状组织TA15合金高温本构关系研究

Study on high temperature constitutive relationship of TA15 alloy with rough lamellar structure

利用THERMECMASTOR-Z型热模拟试验机对粗片层状组织TA15合金进行了变形温度为750～1100℃、应变速率为0．001～10S。的热压缩试验。研究了变形温度、应变速率、应变对流动应力的影响，并采用逐步回归法合理地选取了影响流动应力的“最优”自变量子集，建立了合金的本构关系模型。结果表明，所建立的本构关系模型能够用来表征该合金热变形过程的力学行为；误差分析表明，该逐步回归法本构关系模型具有较高的精度，可用于指导粗片层状组织TA15合金热加工工艺制定，并可用于粗片层状组织TA15合金热变形过程的有限元模拟。

The high temperature compression tests of TA15 alloy with rough tamellar structure were carried on THER- MECMASTOR - Z simulator in the temperature range of 750 - 1100℃ and strain rate range of 0. 001 - 10 s^-1. The in- fluence of deformation temperature, strain rate and strain on the flow stress were studied, and using stepwise regression method to select reasonably the ＂optimal＂ subset of variables which impacted on the flow stress and established constitutive model of the alloy. The results show that the constitutive model can be used to characterize the mechanical behavior during thermal deformation process of the alloy. Error analysis shows that the stepwise regression model for constitutive relationship has higher predicted precision, and it can be used for guiding the hot working process and applied in finite element simulation of TA15 alloy with rough lamellar structure.