Magnesium (Mg) is an attractive material to develop biodegradable parts such as orthopedic devices and cardiovascular stents. Pure Mg suffers from high corrosion rate and relative low strength. To overcome these limitations, grain refinement, textural engineering and alloying are being considered. In the present investigation, an Mg–Zn–Zr (ZK60) alloy, a biocompatible and conventional material, with an initial basal texture component was used. It was deformed at strain rate of 0.01 s–1 via compressive loading to different amounts of strains of 10, 20 and 30 % to study the effects of evolution of basal texture, twinning and second phase particles on the corrosion resistance and shear strength. Microstructural and textural analysis were carried out by scanning electron microscopy and electron backscatter diffraction techniques. As a novel useful method, shear punch test was performed to determine the mechanical strength of the deformed specimens. Corrosion behavior was studied by using electrochemical tests such as polarization and electrochemical impedance spectroscopy. The results exhibited that by increasing the amounts of strain, grain size of the initial un-deformed material decreased, and the basal planes gradually rotated away from the surface. Moreover, second phase particles distributed more uniformly at the whole microstructure. Compressive deformation also resulted in the appearance of extension twins in the microstructure, especially inside the remained coarse grains. Shear strength was enhanced after 10, 20 and 30 % compressive strain due to the finer grain size, more homogenous distribution of particles, and non-basal texture component. The highest corrosion resistance which was at the appropriate range for biomedical applications was obtained in the sample processed via 20 % strain. It was attributed to the finer grain size and an optimum volume fraction of extension twinning, both of which can improve the corroded layer stability and adherence to the substrate.
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