ZnMg0.8Ca0.2 (wt%) biodegradable alloy – The influence of thermal treatment and extrusion on microstructural and mechanical characteristics.

Zinc-based alloys containing the elements of the second group of the periodic table have been extensively studied as potential candidates for applications as a biodegradable material. In this study, the ZnMg0.8Ca0.2 (wt%) alloy was prepared and treated by annealing and extrusion at various conditions. The evolution of microstructure and mechanical properties during annealing and after extrusion was performed in detail. Both annealing and extrusion caused microstructural changes influencing mechanical properties. Annealing caused a homogenization of the microstructure and transformation of metastable phases. The extrusion caused a rearrangement of the intermetallic phases, a refinement and a texturing of the zinc matrix. Those lead to a significant strengthening and to an increase in the ductility, but also to mechanical anisotropy. In this paper, the influence of the processing on the microstructure and mechanical properties is discussed in detail based on the results obtained by various methods, such as scanning and transmission electron microscopy, electron backscattered diffraction, tensile and compressive mechanical testing and nanoindentation. • Solidification mechanism of a ZnMg0.8Ca0.2 (wt%) alloy was proposed. • Formation of Zn-MgZn 2 eutectics was observed. • Influence of annealing and extrusion was studied. • Anisotropy of the extruded alloy was explained. [ABSTRACT FROM AUTHOR]