Precautions for electroplating of die castings

Different alloy materials can be die-casted into different products through different production processes, including aluminum alloy die-casting parts, magnesium alloy die-casting parts, etc., and then processed into finished products through surface treatment, which is a common process.

1. Reduce the defects in the forming of aluminum alloy die castings

Simply put, in the production process of aluminum die castings, it is necessary to avoid surface defects caused by die casting molds, die casting environment (cooling system, pressure system, etc.), die casting machine, manual operation methods, etc. (common defects such as surface sand holes, shrinkage) , Cold pattern, mold corrosion, lack of material, etc.), further affecting the increase in the defective rate of the electroplating process of aluminum alloy die castings.

2. Avoid improper surface polishing and defects

Surface polishing is the primary processing technology before the electroplating of aluminum alloy die castings, and it is also very important. Polishing is to remove some defects on the surface of the black embryo castings, while achieving the purpose of smooth and smooth surface, so that subsequent electroplating is easier. However, this processing process should avoid man-made defects, such as deformation, dimensional changes, etc., and quality control should be strict.

3. Avoid incomplete cleaning before plating, resulting in quality problems after plating

Aluminum alloy die castings need to be ultrasonically cleaned to remove wax and oil before electroplating to achieve a clean surface, which guarantees the reliability of subsequent electroplating. This process must be performed in strict accordance with the operating instructions, and the time, temperature, and sonic parameter settings must meet the process requirements

4. Avoid production of defective products due to poor adhesion

The adhesion of alloy products can be tested by a rigorous hundred grid test to know whether the plating layer is firm. However, because the surface activity of aluminum alloy is not as high as that of zinc alloy, the adhesion of aluminum alloy die castings after electroplating is not so easy to control. The general solution in the industry is to pre-plating before the formal plating, that is, the surface is passivated and the copper base is added, and then the formal plating is performed. This solution is recognized by the industry.

In short, in the electroplating process of aluminum alloy die castings, even if the materials of the die castings are the same, there will be differences in the process due to the operating methods during electroplating. When ensuring the quality of the final surface treatment, you need to calmly analyze and find out the appropriate Solutions to reduce the defect rate in production.