Avoid porosity and shrinkage holes in precision casting of copper castings

In order to avoid porosity in copper castings during precision casting, the mold should be fully preheated, the particle size of the coating should not be too fine, and the gas permeability should be good. Secondly, castings should be cast diagonally. In addition, raw materials should be stored in a well ventilated and dry place.

Shrinkage hole is another rough surface on the outer or inner surface of copper castings. Fine shrinkage pores are dispersed multiple small shrinkage pores, which are the shrinkage, contraction, or contraction of grains. Usually in copper castings, the flow channel is located near the root of the riser, the thicker part, the thicker transition part of the wall, and the thicker part with a large plane.

To avoid shrinkage of copper castings, on the one hand, it is necessary to increase the temperature of the mold; On the other hand, in order to avoid shrinkage of the mold, it is necessary to increase the temperature of the mold, adjust the thickness of the coating, and evenly spray the coating; On the other hand, the mold should be heated or insulated.