Hot deformation behavior and resultant microstructural evolution of dilute Mg-Bi-Sn-Mn alloy during hot compression

This study investigated the dynamic recrystallization (DRX) mechanism and hot-deformation behavior of the solution-treated Mg-0.5Bi-0.5Sn-0.5Mn (BTM000) alloy during hot compression at temperatures ranging from 175 to 225 & DEG;C with a strain rate of 0.001-1 s-1. Processing maps and constitutive equation were used for a detailed analysis. The results showed a strong correlation with a coefficient of 0.987669, indicating the accuracy of proposed method in predicting the hot deformation behavior. The average activation energy (Q) was found to be 139.10 kJ/mol, and the stress component (n) was calculated to be 7.96, suggesting that cross -slip is the primary deformation mechanism. Based on the processing maps, the most suit -able processing conditions were found to be within the range of 210-290 & DEG;C with a strain rate of 0.37-1 s-1. At a low strain rate of 0.001 s-1, the dominant deformation mechanism observed was pyramidal slip. However, at higher temperatures (175-325 & DEG;C) and a strain rate of 1 s-1 , a transformation from basal slip to a combination of basal slip and pyramidal slip was observed. Under low-temperature and low-strain-rate conditions (175 & DEG;C/ 0.001 s-1), continuous dynamic recrystallization (CDRX) was the dominant mechanism. In contrast, under other deformation conditions (175 & DEG;C/1 s-1, 325 & DEG;C/0.001 s-1, 325 & DEG;C/1 s-1), a synergistic effect between discontinuous dynamic recrystallization (DDRX) and CDRX was evident. Through quasi-situ kernel average misorientation (KAM) characterization, it was observed that the local storage energy associated with CDRX was significantlylowercompared to the combination of CDRX and DDRX, indicating a higher likelihood of CDRX occurrence.& COPY; 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This study investigates the dynamic recrystallization mechanism and hot deformation behavior of the Mg-0.5Bi-0.5Sn-0.5Mn alloy. The results show a strong correlation and suggest that cross-slip is the primary deformation mechanism. The processing maps indicate the most suitable processing conditions, and the occurrence of continuous and discontinuous dynamic recrystallization under different deformation conditions is observed.