Surface treatment process for die casting

Abstract

The invention discloses a surface treatment process for a die casting. The surface treatment process comprises the following steps of (1) die-casting forming of a workpiece, (2) polishing, (3) cleaning, (4) drying, (5) sand blasting or wiredrawing, (6) pretreatment, (7) anodizing, (8) coloring and (9) hole sealing. In the step (1), the workpiece is made into the die casting through die-casting forming, and the die casting is die-casting aluminum alloy lower than 1% in silicon content. According to the surface treatment process for the die casting, a product with a high-texture appearance is made on the surface of the die casting, thus the appearance of the die casting achieve a good anticorrosion effect and rich colors, and process cost is low.

Description

technical field [0001] The invention relates to the technical field of metal processing, in particular to a surface treatment process for die castings. Background technique [0002] Die-casting technology is a common metal casting processing technology. It has high processing precision and good strength, and can realize structural parts with complex shapes. It also has significant advantages such as high material utilization rate and high production efficiency. Therefore, with the processing technology of metal appearance parts With the development of the industry, the die-casting process is gradually applied to the processing of metal appearance parts, such as the processing of mobile phone casings. [0003] However, due to the characteristics of the die-casting process itself, various surface defects such as air bubbles, flow marks, sand holes and dark lines will be produced in the metal appearance parts during the die-casting process, so the good products of the die-casti...

AI Technical Summary

Problems solved by technology

[0005] (1) Painting and powder spraying: the cost is expensive, and the metal appears plastic after spraying, the metal effect is not obvious, and the required metal texture cannot be achieved;

[0006] (2) Electroplating: It can achieve corrosion resistance effect, but the electroplating color is single, most colors cannot be realized by electroplating process, and the appearance cannot meet customer requirements;

[0007] (3) Film: it will make the die casting lose its metal texture

[0008] The anodizing process can obtain better metal texture and rich colors, but the metal material used for die-casting determines that the die-casting parts cannot be treated with high-quality surface treatment. For example, the existing die-casting aluminum alloy (such as ADC12) contains silicon, iron, etc. Composition, resulting in extremely poor anodic oxidation effect of die-casting aluminum alloy, zinc alloy and magnesium alloy also have the same problem of poor anode effect