Microstructure refinement by a novel friction-based processing on Mg-Zn-Ca alloy

Insufficient mechanical properties and uncontrollable degradation rates limit the wide application of Mg alloys in bioimplant materials. Microstructure refinement is a common method to improve both the mechanical properties and the corrosion resistance of Mg alloys. In order to efficiently obtain Mg alloys with fine microstructures for potential applications in bioimplant materials, a novel constrained friction processing (CFP) was proposed. In this work, the resulting compression properties of ZX10 alloy obtained by CFP with optimized processing parameter are reported. Additionally, the microstructure evolution during CFP was studied. The results show that during CFP, materials are subjected to high shear strain at the transition zone between the stir zone and thermo-mechanical affected zone, leading to recrystallization with strong local basal fiber shear texture. As the shoulder plunges down, the fraction of recrystallized grain and grain size increase. ZX10 alloy obtained by CFP exhibited higher compressive yield strength by more than 300% and ultimate compressive strength improves by 60%, which indicates the bright prospect of CFP for Mg processing.