A novel
scandium-containing cast aluminum-
lithium alloy is disclosed. The
alloy includes, by weight, 1.6-1.99% of Li, 0.9-1.9% of Cu, 0.2-0.7% of Mg, 0.1-0.25% of Zr, 0.05-0.35% of Sc, and
impurity elements which are Fe, Si, Na, K and P, with the balance being Al, with the
Fe content being less than 0.15% and the total content of the
impurity elements being less than 0.25%. During preparation, Al-Cu and Al-Zr master alloys, pure aluminum, pure Mg and pure Li are smelted to obtain an aluminum
alloy; then three stages of
solid solution heat treatment are performed including
solid solution heat treatment at 440-460 DEG C for 32 h,
solid solution heat treatment at 510-520 DEG C for 24-32 h and
solid solution heat treatment at 530-540 DEG C for 1-6 h; and after water
quenching, artificial
ageing treatment at 150-190 DEG C is performed for 16-48 h to obtain the novel
scandium-containing cast aluminum-
lithium alloy. The obtained novel
scandium-containing cast aluminum-
lithium alloy has a uniform microscopic structure, stable performance, density lower than density of traditional aluminum alloys, higher
elastic modulus and rigidity, and other mechanical properties, and is low in cost. Theultimate tensile strength of the novel scandium-containing cast aluminum-lithium alloy can be 450-490 MPa and the specific elongation is 4.5-7.0%.