The invention discloses a
magnesium alloy and a method for preparing the same. The weight percentage compositions of the
magnesium alloy as follows: 7 to11 percent by weight of Gd, 2 to 5 percent by weight of Y, 0.3 to 0.6 percent by weight of Zr, 0 to 1.0 percent by weight of Zn, the balance Mg and incidental
impurity elements. The method for preparing the
alloy comprises alloy melting, refining,
casting,
solid solution,
extrusion deformation and two
artificial aging methods, to produce
heat resistant magnesium alloy extruded bar with high strength and high
toughness. The tensile properties of the
magnesium alloy at
room temperature manufactured by adopting direct
artificial aging is: tensile strength sigma b is between 450 and 480 MPa, sigma 0.2 is between 390 and 425 MPa,
delta 5 is between 3 and 5 percent; when test specimen is heated to 250 DEG C for 10 min, the tensile strength sigma b is more than or equal to 300 MPa. The tensile properties of the
magnesium alloy at
room temperature manufactured by adopting dual
artificial aging is: tensile strength sigma b is between 380 and 395 MPa, sigma 0.2 is between 280 and 290 MPa,
delta 5 is between 15 and 21 percent; when test specimen is heated to 250 DEG C for 10 min, the tensile strength sigma b is more than or equal to 260 MPa. The invention produces the
heat resistant magnesium alloy of high strength and high
toughness with the density of no more than 1.93g / cm3, which can satisfy the demands of density, strength and
toughness, and
heat resistance of
metal materials in specific fields.