Electrochemical behavior of a magnesium ZK60 alloy processed by high-pressure torsion

•Electrochemical behavior of a ZK60 Mg alloy processed by HPT was examined.•Inhomogeneous grain refinement due to straining leads to micro galvanic cells.•Additional straining with fine and uniform grains decreased the corrosion rate.•Integrated homogeneous oxide film hindered the active dissolution of substrate. High-pressure torsion (HPT) was used to evaluate the effect of straining on the electrochemical properties of a ZK60 magnesium alloy. The samples were processed using HPT up to 20 turns and the electrochemical responses were examined through polarization, EIS, Mott–Schottky and hydrogen evolution tests. Electron back-scatter diffraction (EBSD) studies showed more homogeneity with finer average grain sizes accompanied by the evolution of a nobler texture when increasing the numbers of HPT turns. Ultimately, this led to improved corrosion behavior for the HPT-processed disks. Post corrosion observations revealed improved protective layers after higher turns of HPT.