Effect of free-end torsion on microstructure and mechanical properties of AZ31 bars with square section

In this study, a rolled AZ31 bar with square section was used. The reciprocating torsion was performed to maintain the shape of the sample. The microstructure evolution of AZ31 bar during torsion and its influence on compressive anisotropy were investigated in detail. Results showed that reciprocating torsion can simultaneously enhance yield strength in three compressive directions, and reduce compressive anisotropy. Reciprocating torsion generated profuse dislocations and {10-12} twin boundaries to harden the micro-hardness and yield strength. Reciprocating torsion can also generate new texture component which is mainly from the orientation of newly generated {10-12} twins. The new twin-structures will be responsible for the reduction in compressive anisotropy. Moreover, uneven deformation features in twisted sample were systematically investigated. (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

This study found that reciprocating torsion can enhance yield strength in three compressive directions simultaneously, and reduce compressive anisotropy. Reciprocating torsion generates profuse dislocations and {10-12} twin boundaries to harden the micro-hardness and yield strength.