利用本构方程和加工图表征BFe10-1-2白铜合金的热变形行为

Characterization of high temperature deformation behavior of BFe10-1-2 cupronickel alloy using constitutive equation and processing map

摘要:

为了获得BFe10-1-2白铜合金的合理热变形工艺参数,通过热模拟压缩试验对该合金的高温变形行为进行了研究。试验温度为1023~1273K,应变速率为0.001~10s_-1。通过流变曲线分析、动力学分析及加工图对BFe10-1-2白铜合金的高温变形行为进行了表征,计算出BFe10-1-2白铜合金在热压缩变形过程中的激活能为425.299KJ/mol。通过Zener-Holloman参数以及真应变建立了BFe10-1-2白铜合金的本构方程用以描述该合金的高温流动应力。对计算的流动应力值与试验值进行了对比,结果表明：本构方程可以准确描述该合金的高温流动行为。此外,基于动态模型,建立了BFe10-1-2白铜合金的热加工图,并通过宏观及微观组织分析对加工图的准确性进行了验证。

Abstract:

High temperature deformation behavior of BFe10-1-2 cupronickel alloy under compression in the temperature range of 1023~1273K and strain rate range of 0.001~10s-1 were investigated for the sake of acquiring the optimum hot deformation processing parameters. The high temperature deformation behavior of BFe10-1-2 cupronickel alloy was characterized based on the analysis of the flow stress, kinetics and processing map. The activation energy for deformation obtained during high temperature compression of BFe10-1-2 cupronickel alloy was 425.299KJ/mol. A constitutive equation was then developed to describe the flow stress as a function of Zener-Holloman parameter and true strain. By comparing the calculated flow stress and the measured flow stress, the validity of the constitutive equation was verified. The results showed that the flow stress values obtained from the constitutive equation could track the experimental results. Thereafter, the processing map based on dynamic materials model was established, and the validation of processing map was investigated from the macro appearance and microstructure of compressed BFe10-1-2 cupronickel alloy.