Electroplating surface treatment of Zinc alloy casting is very important. If the electroplating is not done well, then all the work in the early stage will be wasted. So it is important to pay attention to the product electroplating. Then, what factors can affact the electroplating quality? They are summarized as follows:
1. The choice of raw material for zinc alloy die casting must be made of normal national standard material.
2. The design of zinc alloy die casting should be reasonable. The shape should take into account the covering ability of electroplating, so as to reduce the perforation as far as possible, and make washing solution not easy to carry. Reduce sharp angle and other parts, so that the distribution of power lines in electroplating is even.
3. Die casting process, and die casting mold design should be reasonable, so that die casting does not occur shrinkage holes, pinholes and loose and other shortcomings, because the shortcomings will directly affect the coating adhesion.
4. In the production process of zinc alloy die casting, segregation should be reduced as far as possible. Such as some parts of the aluminum segregation, in degreasing, the first aluminum dissolution, and in the appearance of the die casting produce pores, pinholes which can not be washed to result in poor adhesion and result in coating peeling bubbles.
5. During the grinding and polishing processof the die casting process, it is important to pay attention to grasp the inch. In addition, the die-casting surface cooling process of the formation of 0.05 ~ 0.1mm of the fine layer is very important for electroplating, grinding and polishing to reduce the loss of the fine layer as far as possible. If the layer of grinding is taken away, the porous structure will be exposed, and there will not be a good electroplating layer.
6. Composed of many kinds of electroplating copper - nickel - chromium coating, relative to the substrate is a negative plate coating, as long as the mechanical maintenance effect, and zinc alloy corrosion in the humid air, so it is necessary to ensure that the coating without holes. Otherwise zinc alloy corrosion products will make the coating bubbling. The coating should be thicker than that of steel parts before it is suitable for zinc alloy die casting.
7. The residuum of die casting and machining should be cleaned as far as possible after processing. As the residue is active metal, in any process of electroplating, it will react with the solution, and damage the plating solution, constitute the impact on the quality of electroplating.