What Are The Precautions For Surface Treatment Of Sheet Metal Processing

[Deno Jenelle]

the decorative and protective effect of the surface treatment of sheet metal processing process on the product surface is recognized by many industries. In the sheet metal processing industry, the commonly used surface treatment methods include electroplating, spraying and other surface treatment methods

1. Electroplating is divided into: zinc plating (color zinc, white zinc, blue zinc, black zinc), nickel plating, chromium plating, etc; It mainly forms a protective layer on the surface of the material to protect and decorate

2. Spraying is divided into spray painting and powder spraying. After the material is pretreated, spray the coating onto the surface of precision sheet metal workpiece with spray gun and gas, and the coating forms a coating on the surface of workpiece After drying, it plays a protective role& nbsp;

3. Other surface treatment methods: anodic oxidation, chromate, wire drawing, milling operation sand blasting, oxidation, etc

precautions

1 All electrochemical treatment shall be carried out in the state of parts, because the chemical solution in the treatment process will be trapped in the gap of the assembly and cause corrosion

2. Spot welded parts can be subject to chemical treatment, but not electrochemical treatment (including electroplating and anodizing)

3. Aluminum alloy castings cannot be anodized with sulfuric acid

4. Thin and long tubular parts (whose length is greater than twice the diameter) are generally not suitable for electrochemical treatment, because there will be no film on the inner surface; (special measures can be taken to meet the requirements under special circumstances)

5 After electroplating, the inner surface of parts with deep grooves or fine holes (generally refers to the depth greater than twice the diameter or opening width, but the excellent process is not subject to this limit), the coating will not be completely covered

6 It is better to carry out phosphating treatment before spraying steel parts to increase the adhesion of the coating

7. In order to improve the corrosion resistance of steel parts plated with bright nickel, copper or dark nickel can be plated first

8. Zinc base alloy generally adopts electroplating layer as protective decoration. In order to improve the adhesion of its coating, copper or nickel should be pre plated first

9. Since most organic gases have corrosive effect on zinc, the zinc coating should be carefully selected in the design of sheet metal processing to contact with organic materials or assembled in the same closed body

10. For electroplated (oxidized) parts with riveting requirements, the processing process must be electroplated (or oxidized) first and then riveted