Effect of Sn microalloying on the hot deformation behavior of Mg-Gd-Y-Zn-Zr alloy

The necessary condition for using plastic forming to regulate microstructure is a sufficient understanding of the material's hot deformation behavior. This work systematically studied the mechanical response and micro- structural evolution of Mg-8Gd-5Y-1.5Zn-0.5Zr(-0.3Sn) alloys during hot compression, and established corresponding mathematical models, which provide data sources and theoretical support for subsequent plastic forming simulations and process parameter optimization. Sn microalloying induces the formation of numerous submicron sized (31 particles during hot compression, which is related to the ease of bonding between Sn and rare earth (RE) elements. The (31 particle swarm promotes recrystallization by activating the particle-stimulated nucleation (PSN) mechanism, so that the flow stress decreases to steady state with a greater magnitude after reaching its peak. Sn microalloying allows Mg-Gd-Y-Zn-Zr alloys with poor formability to achieve more effective grain refinement at relatively low strains.