LAUSR

Abstract The microstructure, mechanical properties, damping capacities and corrosion properties of Mg-8.5Gd-5Y-xAl (x = 0.2, 0.5, 0.8 and 1.1 wt%) alloys were investigated in this study. The results revealed that the alloys were mainly composed by long period stacking ordered(LPSO) phase, Mg-RE phase, Al-RE phase and magnesium(Mg) matrix. With the increase of Al content, the LPSO phase decreases. After extrusion, Mg-8.5Gd-5Y-0.2Al shows the best mechanical properties and damping performance, with the tensile strength of 376 MPa, yield strength of 263 MPa, elongation of 13%, the Q-1 is 0.0132 when the strain is 1×10-3. The corrosion properties also show that with the Al content increasing, the corrosion rate increases. Mg-8.5Gd-5Y-0.2Al shows the lowest corrosion rate of 3.80 mm per year and the lowest corrosion current density of 2.81 × 10-5 A/cm2. The LPSO phase can enhance the mechanical properties and corrosion resistance at same time.