The purpose of surface treatment of die-casting parts is to select appropriate skills according to specific requirements to obtain a high-quality film layer that meets the requirements. Since the existing various surface treatment skills still have their own problems, to achieve this goal, you should have an understanding of the key issues in different treatment skills.

1. Key skills in chemical film formation

Since the chemical film formation is carried out by completely relying on the chemical reaction between the treatment liquid and the workpiece, it does not have the effect of an applied voltage like the anodic oxidation film formation. In addition to the operating procedures, full attention should be paid to the uniformity of the die casting surface. Only a surface with uniform composition can form a uniform treatment film, so it should be ensured that the composition of the magnesium alloy liquid is uniform, the composition of the die-casting part is uniform, and the surface of the die-casting part is sufficiently clean. When thin-walled (less than 2mm) die castings are processed, the design of alloy liquid composition, injection speed, and mold conditions that affect the uniformity of the surface composition of the die castings should be strictly controlled to ensure the uniformity and stability of the surface components of the die castings.

2. The key skills in anodizing film formation

Since the anodic oxidation film formation is carried out under the action of an applied voltage, the surface quality requirements of this technology are not as stringent as those of chemical film formation. A suitable processing voltage and processing time can always be found to obtain a high-quality film. Regarding the anodic oxidation film formation, the most critical issue is the effectiveness of the treatment solution. The decrease in the surface quality requirements of die-casting parts gives the release agent a chance to enter the treatment liquid. If the selection of the release agent and the treatment liquid do not match, it will lead to the rapid failure of the treatment liquid. During the process, the temperature of the treatment liquid will rise rapidly, which will lead to the failure of some treatment liquids and affect the surface treatment effect. Therefore, the rational selection of mold release agent and treatment liquid, and keeping the temperature of treatment liquid constant are the key technical problems of anodic oxidation film formation.