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In the process of zinc die casting, Zinc Alloy Die Casting, the problem of shrinkage cavity and porosity is really big and troublesome. What is the cause of the formation of shrinkage cavity and porosity? And what is the solution to solve it completely for Die Casting Products? Shrink cavity and porosity are formed in such a way that if the liquid alloy poured into the casting mold development is not replenished during the subsequent solidification by liquid shrinkage and solidification shrinkage, holes are formed in the solidified parts of the zinc alloy die casting.The cavity with large volume is called shrinkage cavity, and the cavity with small and scattered volume is called porosity cavity. Generally appear in the solidification part of the upper part of the casting, the shape is mostly inverted cone, the inner surface is rough, usually hidden in the inner layer of the casting.The narrower the crystallization temperature range, the more the casting alloy is inclined to solidify layer by layer, and the easier it is to form shrinkage cavity. Firstly, the liquid alloy fills the casting mold for die casting products. Due to the action of the casting mold, a layer of liquid alloy near the surface of the casting mold quickly solidifies, while the interior remains in the liquid state.As the temperature of the casting continues to drop, the thickness of the shell continues to increase, and the volume of the internal liquid alloy decreases due to its own liquid shrinkage and the solidification shrinkage of the supplementary shell, resulting in a drop in the liquid level and a gap in the zinc die casting zinc alloy die casting. In this way, the casting layer by layer solidification, until the complete solidification, in its upper part to form a shrinkage cavity. Solid-state shrinkage will reduce the external size of zinc alloy die castings slightly. In short, the larger the liquid shrinkage and solidification shrinkage of zinc alloy, the larger the volume of the shrinkage cavity.