Influence of heat treatment and hot rolling on the microstructure and texture development of the Mg–Dy–Nd–Zn–Zr alloy Resoloy

This study investigates the influence of heat treatment and hot rolling on the microstructure and texture development of the magnesium alloy Resoloy ® , which was specifically designed for biomedical applications. The alloy was subjected to various heat treatment conditions (375 °C to 500 °C for 15 min to 6 h) and subsequently hot-rolled at equivalent strains ranging from 0.23 to 0.75 and equivalent strain rates from 24 to 183 s⁻ 1 . Suitable preparation for hot rolling was achieved with heat treatment at 500 °C for 2 h, which facilitated reduced hardening and minimized crack formation at higher strains and strain rates. Microstructural analysis revealed the presence of lamellar long-period stacking ordered (LPSO) phases, twins, and kinking bands. While clear evidence of recrystallized grains is lacking, indications of continuous dynamic recrystallization (CDRX), twinning-induced dynamic recrystallization (TDRX), particle stimulated nucleation (PSN) and kink-aided dynamic recrystallization (KDRX) as the primary recrystallisation mechanisms are observed as well as the influence of the precipitated LPSO phase. Whilst the 18R phase seems to propagate dynamic recrystallisation, the 14H phase seems to hinder it. Texture analysis indicated a reduction in maximum intensity and the activation of non-basal slip systems during hot rolling. Heat treatments between 375 and 500 °C led to slight hardness increases, while prolonged treatment at 500 °C reduced hardness due to precipitate dissolution. Hot rolling further enhanced hardness, especially with the formation of the 14H phase, which supports grain boundary strengthening.