According to relevant media reports, due to the loose structure and high porosity of aluminum castings, which contain various metal and non-metal impurities, white spots are prone to appear on the anodized film after dyeing, and the quality of anodized film on aluminum castings is difficult. Experts suggest that the following methods can be used to avoid this problem: using high-voltage and high current density impact method. In the early stage of anodizing, high voltage and high current are applied to connect the small and large "islands" that were originally divided by impurities into pieces through high current impact. Secondly, the surface polishing method for castings. Grinding can fill the pores of castings with aluminum powder, serving as a bridge connecting the isolated "islands" of impurities. Thirdly, the surface shot blasting method for castings. Before using the shot blasting method, the author used a round headed hammer to strike, with the original intention of closing the gaps that block the "islands" by striking, achieving the goal of connecting them into pieces. The result was significant. These methods can effectively prevent white spots from appearing on the anodized film of aluminum castings after dyeing, thereby improving their quality.
Aluminum casting anodized film dyeing into casting enterprises urgently need to curb the problem
2025 07/18