The invention discloses an air blower and a preparation technique thereof, and belongs to the technical field of metal materials. The air blower comprises 0.5-1.5% of Li, 0.1-0.3% of Pt, 0.1-0.3% of Ir, 2-4% of Ni, 0.5-1.5% of Mg, 1-5% of Cu, and the balance Al and impurities. The chemical activity of Li of the raw materials is high and can react with gas elements such as hydrogen, oxygen, sulfurand nitrogen in alloy to generate a chemical compound with a low density and a low melting point, and bubbles and other defects of metal are eliminated. Pt and Ir are likely to form a Pt-Ir binary alloy phase, the expansion coefficient is small, and thus the capacity to resist thermal expansion and cold contraction of aluminum alloy can be improved. Meanwhile, grains are refined through solid solution treatment and aging treatment, so that the alloy has a good mechanical property. A uniform and compact ceramic-like film is formed on the surface of a product through micro-arc oxidation, and thus the product has extremely high resistance in complex and changeable environments.