AlSiLi phase aging strengthening type low-density aluminum alloy and preparation method thereof

The invention discloses an AlSiLi phase aging strengthening type low-density aluminum alloy and a preparation method thereof, and belongs to the technical field of nonferrous metal preparation and processing. The aluminum alloy comprises the following basic components in percentage by weight: 0.01%-1.0% of Si, 0.01%-1.0% of Li and the balance of Al, and at least one of the following elements in percentage by mass: 0.01-1.0% of Mg, Ca, Sr, Ti, B, Cu, Zn, Mn, Ag, Sc, Zr, Fe, Cr and Ge can be further added; the microstructure of the aluminum alloy is characterized in that AlSiLi precipitated phases with the size smaller than 30 nm are dispersed and distributed in an aging peak state aluminum matrix, and a remarkable aging strengthening effect is achieved. The preparation method comprises the steps of die casting, high-temperature solid solution treatment and aging heat treatment, or casting, high-temperature solid solution, plastic deformation and aging heat treatment, or atomization powder preparation, 3D print