Novel surface treatment method for improving corrosion resistance of aluminum casting

The invention discloses a novel surface treatment method for improving the corrosion resistance of an aluminum casting. The method comprises the following steps of: 1) pretreating, namely deoiling and dedusting the aluminum casting; 2) chromating, namely chromating the aluminum casting by a chemical chromating process, so that a chromate layer is formed on the surface of the aluminum casting; 3) performing top coat treatment, namely drying the chromated aluminum casting for the first time, spraying a top coat adhesive on the surface of the aluminum casting to form a top coat adhesive layer, and drying for the second time; 4) performing base coat treatment, namely spraying a base coat adhesive on the surface of the aluminum casting subjected to top coat treatment to form a base coat adhesive layer; 5) curing, namely curing the top coat adhesive and the base coat adhesive which are coated on the surface of the aluminum casting; and 6) cooling, namely cooling the cured aluminum casting at room temperature. By the novel surface treatment method for improving the corrosion resistance of the aluminum casting, the corrosion resistance of the aluminum casting is greatly improved, a test proves that neutral salt spray resistance time is more than 500 hours, and the application range of the aluminum casting is expanded.