Hot Deformation Behavior of Cu-2.7Be Alloy during Isothermal Compression

Abstract

The hot deformation behavior of Cu-2.7Be alloy was studied through isothermal hot compression experiments under various temperature and strain rate conditions. To predict and investigate the flow stress behavior, modified Johnson–Cook, Arrhenius-type, and artificial neural network models were used. The predictabilities of the models were assessed considering the parameters of average absolute relative error, correlation coefficient, and relative error. Among the three constitutive models, the ANN model was revealed to be the most accurate. According to the results of the dynamic material model theory, the hot processing of Cu-2.7Be alloys achieved its maximum efficiency (~60%) under a strain rate of 0.6 s−1, temperature range of 1023-1073 K, and the logarithm of strain rate in the range (− 1.25)-(− 0.25) s−1. Microstructural analysis indicated that the temperature and strain rate factors significantly affected the primary dynamic softening mechanism of the Cu-2.7Be alloys, following hot compression processing. At temperatures below 973 K, the Cu-2.7Be alloy primarily obeyed the dynamic recovery mechanism. Furthermore, the predominant mechanisms followed by the samples under the temperature/strain rate conditions of 973/0.1 and 1073 K/0.1 s−1 were continuous dynamic recrystallization and discontinuous dynamic recrystallization, respectively.