Effect of extrusion temperature on dynamic recrystallization behavior and mechanical properties of flame-retardant Mg-Al-Ca-Zn-Sn-Mn alloy

The effect of extrusion temperature on the dynamic recrystallization behavior and mechanical properties of the flame-retardant Mg-6Al-3Ca-1Zn-1Sn-Mn (wt.%) alloy was investigated. The observed dynamic recrystallization mechanisms in the alloy include continuous dynamic recrystallization (CDRX) and particle simulated nucleation (PSN) during hot extrusion. A significant increase in yield strength, from 218 to 358 MPa, representing a 140 MPa increase, is achieved by decreasing the extrusion temperature. The strengthening mechanisms were analyzed quantitatively, with the enhanced strength primarily attributed to grain boundary and dislocation strengthening. The plasticity mechanism was analyzed qualitatively, and the increase in the volume fraction of unDRXed grains caused by the decrease in extrusion temperature leads to an increase in the number of {102} tensile twins during the tensile deformation, resulting in a reduction in plasticity.