What are the precautions for electroplating of aluminum alloy die castings
Different alloy materials can be diecasted into different products through different production processes, including aluminum alloy die castings, magnesium alloy die castings, etc., and then processed into finished products through surface treatment. As a common process, the electroplating surface treatment of aluminum alloy die castings is complex. Yi'an Technology reminds you that the following issues should be paid attention to during the processing.
1. Reduce the defects of aluminum alloy die castings during molding
To put it simply, in the production process of aluminum die castings, it is necessary to avoid the occurrence of surface defects (common defects such as surface sand holes, shrinkage, cold lines, mold erosion, lack of material, etc.) caused by unsuitable die-casting molds, die-casting environment (cooling system, pressure system, etc.), die-casting machines, human operation methods, etc., which further affect the rise of defective rate in the electroplating process of aluminum alloy die castings.
2. Avoid defects caused by improper surface polishing
Surface polishing is the primary processing technology for aluminum alloy die castings before electroplating, and it is also very important. Polishing is to remove some defects on the surface of black embryo castings, and achieve the purpose of flat and smooth surface, so that subsequent electroplating is easier. However, this processing process should avoid man-made defects, such as deformation, size changes, etc., and the quality control should be strict.
3. Avoid the occurrence of quality problems after plating due to incomplete cleaning before plating
Before electroplating, aluminum alloy die castings need to be cleaned by ultrasonic wave to remove wax and oil, so as to achieve a clean surface and guarantee the reliability of subsequent electroplating. This process should be carried out in strict accordance with the operation instructions, and the time, temperature and acoustic wave parameters should be set in accordance with the process requirements.
4. Avoid defective products with poor adhesion
The adhesion of alloy products can be tested by rigorous hundred grid test to know whether the electroplating coating 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 easy to control. The general solution in the industry is to conduct pre plating treatment before formal plating, that is, passivating the surface and adding copper base, and then conducting formal electroplating. This scheme has been recognized by the industry.
In a word, in the electroplating process of aluminum alloy die castings, even if the die casting materials are the same, there will be differences in the electroplating process due to the operation methods. When ensuring the product quality after the final surface treatment, it is necessary to calmly analyze and find out the appropriate solution to reduce the defective rate in production.

A80 sliding window powder coating extrusion profile