The invention relates to a novel damage-resistant aluminum-
lithium alloy and a preparation method thereof. The
alloy comprises the following components in percentage by weight: 2.8 to 4.0 percent of Cu, 0.8 to 1.9 percent of Li, 0.20 to 0.60 percent of Mn, 0.20 to 0.80 percent of Zn, 0.04 to 0.20 percent of Zr, 0.20 to 0.80 percent of Mg, 0.1 to 0.7 percent of Ag, less than or equal to 0.10 percent of Si, less than or equal to 0.10 percent of Fe, less than or equal to 0.12 percent of Ti, less than or equal to 0.15 percent of other impurities, and the balance of Al, wherein a single
impurity accounts for less than or equal to 0.05 percent of the weight of the
alloy; and one to five of alloy elements Mn, Zn, Mg, Ag and Zr can be selectively added. The preparation method comprises the following steps of: mixing the alloy elements, melting raw materials, performing furnace refining, standing, and pouring to form alloy ingots with required specifications. The alloy ingots are formed by hot
extrusion, hot rolling and cold rolling after being optimized and homogenized and are used for machined parts after being subjected to heat treatment by an optimal process. The novel damage-resistant aluminum-
lithium alloy material of the invention has a uniform
microstructure and stable performance and is suitable for manufacturing sheets. Products made of the material can be used for structural elements in the fields such as
aerospace,
nuclear industry, transportation, sports goods, weapons and the like.