Therefore, cleaning the surface of copper castings and strengthening the appropriate process steps are the key to solving the silver plating quality of copper castings. Because the metal structure of copper castings is loose and porous, attention should be paid to the cleaning of each process during the electroplating process to prevent the solution remaining in the hole from affecting the next process; during electroplating, the impulse current density is about 3 times higher than that of ordinary parts, and the pre-plating time is longer than ordinary parts.

The high-precision copper strip used for the special-shaped frame of the cast copper transistor is generally made of a high-strength, high-conductivity alloy containing phosphorus and silver, and its section is composed of thick and thin sides. The blanks with special-shaped cross-sections are produced through pass rolling, chip milling, and high-speed forging, and then high-precision rolling is carried out to ensure that the elongation coefficients of the thick edges and thin joints are equal, otherwise the shape of the special-shaped strip cannot meet the needs of users.

The microstructure of copper castings is looser than that of rolled and rolled copper, and the appearance is rough and porous. To avoid or reduce defects such as component segregation, deformation and cracking of copper castings. When designing copper castings, not only must the geometric shape and size be determined according to the working conditions and the properties of the metal material, but also the rationality of the design must be considered from the perspective of the casting alloy and the characteristics of the casting Casting Automotive Mould Manufacturers process, that is, the obvious size effect and the problems of solidification, shrinkage, stress, etc.

When precasting, the parts and hanging tools should be shaken frequently to ensure the uniform color of the coating and prevent the appearance of spots during silver plating, which will affect the appearance of the coating; under the premise of shaking the workpiece, electroplating with pulse current density for 5 minutes, and then change to normal current density . In addition, some molding sand, paraffin and silicate substances often remain on the surface of copper castings, which often leads to local electroplating

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