Microstructures and mechanical properties of as-extruded Mg–5Sn–1Zn–xAl (x=1, 3 and 5) alloys

As-extruded Mg–5Sn–1Zn–xAl alloys (x=1, 3, and 5) were fabricated by hot extrusion. The experimental results revealed that the yield strength of alloys initially decreased and then increased with the increase of Al content. These changes were mainly attributed to the difference in crystallographic texture and volume fractions of second phases. The ultimate tensile strength, yield strength, and elongation of the alloys were greater than 310 MPa, 227 MPa, and 11%, respectively. The strain hardening ability of the alloys was also discussed.