The invention provides an ultra-light high-modulus high-strength
casting aluminum-
lithium matrix composite and a preparation method thereof. The aluminum-
lithium matrix composite comprises a matrix
alloy and a strengthening phase, the matrix
alloy comprises the following elements of, by
mass, 2.5%-3.5% of Li, 1%-2.5 % of Cu, 0.4%-0.5% Mg, 0.15%-0.2% of Sc, 0.15%-0.2% Zr, 0-0.2% of Cd, less than 0.2% of the total content of
impurity elements and the balance Al; and the strengthening phase is TiB2. The preparation method comprises the steps that Ti B2 / Al
base metal alloy is prepared by using in-situ synthesized reaction; and then the TiB2 / Al
base metal alloy, pure aluminum and Al-Cu, Al-Li and other intermediate alloys are smelted to obtain a composite, and after specific
solid solution andaging treatment are carried out, the ultra-light high-modulus high-strength
casting aluminum-
lithium matrix composite is obtained. The ultra-light high-modulus high-strength
casting aluminum-lithium matrix composite has higher strength and
elastic modulus and lower density, and has lower cost meanwhile.