Abstract AZ91 Mg alloys were processed by equal channel angular extrusion (ECAE) up to 4 passes through route-R. The increase in number of ECAE passes to yield fine-grain structure in the bulk Mg alloy with a more dislocation density, this enhances mechanical properties and corrosion resistance. Indeed, microstructural observations revealed an equiaxed and significant grain refinement after ECAE-4P, with a mean grain size (d) of ∼ 4.36μm. Further, the tensile strength, micro-hardness and corrosion resistance were …