Effect of LPSO structure on mechanical properties and corrosion behavior of as-extruded GZ51K magnesium alloy

• LPSO structure is formed in the as-extruded GZ51K alloy.
• As-extruded GZ51K exhibits high elongation (30.7%).
• As-extruded GZ51K has good corrosion resistance and uniform corrosion mode.
• The distribution of the LPSO impacts the corrosion behavior of GZ51K alloy.

Mechanical properties and corrosion behavior of the as-extruded Mg-5Gd-1Zn-0.6Zr (GZ51K) alloy with long period stacking ordered (LPSO) structure were investigated and compared to those of the solution treated alloy without LPSO structure. Yield strength and elongation are significantly improved after extrusion, as well as ultimate tensile strength and microhardness. The as-extruded alloy exhibits much slower corrosion rate and more uniform corrosion morphology mainly due to grain refinement, absence of Zr-rich phase, and formation of the LPSO structure.