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论文类型：期刊论文

发表时间：2016-03-01

发表刊物：HIGH TEMPERATURE MATERIALS AND PROCESSES

收录刊物：SCIE、EI、Scopus

卷号：35

期号：3

页面范围：327-336

ISSN号：0334-6455

关键字：Nimonic 80A; constitutive model; flow stress; dynamic recrystallization; hot deformation

摘要：The hot deformation characteristics of nickel-based alloy Nimonic 80A were investigated by isothermal compression tests conducted in the temperature range of 1,000-1,200 degrees C and the strain rate range of 0.01-5 s(-1) on a Gleeble-1500 thermomechanical simulator. In order to establish the constitutive models for dynamic recrystallization (DRX) behavior and flow stress of Nimonic 80A, the material constants a, n and DRX activation energy Q in the constitutive models were calculated by the regression analysis of the experimental data. The dependences of initial stress, saturation stress, steady-state stress, dynamic recovery (DRV) parameter, peak strain, critical strain and DRX grain size on deformation parameters were obtained. Then, the Avrami equation including the critical strain for DRX and the peak strain as a function of strain was established to describe the DRX volume fraction. Finally, the constitutive model for flow stress of Nimonic 80A was developed in DRV region and DRX region, respectively. The flow stress values predicted by the constitutive model are in good agreement with the experimental ones, which indicates that the constitutive model can give an accurate estimate for the flow stress of Nimonic 80A under the deformation conditions.