News

Alloy castings should pay attention to these details

In recent years, alloy die casting manufacturers can be said to be more and more, in the era of rapid development of science and technology, machinery and equipment are constantly updated, more and more mechanical castings in short supply, so there will be so many die casting manufacturers.

The main defect is protruding vesicles on the surface of the mold. Exposed after polishing or finishing after fuel injection or plating.

The cause of foaming defects in castings is that the holes are mainly caused by pores and shrinkage mechanism, and the pores are often circular and irregular. The cause of porosity is that during the filling and solidification process of liquid metal, the inner surface or inner hole of the casting is invaded by the coating volatile gas caused by gas intrusion.

During solidification, the gas content of the alloy liquid is too high.

When the gas in the cavity is emitted by the paint by the gas solidified by the alloy when the mold is exhausted, the pores formed in the casting can remain.

Zinc alloy die casting parts are widely used in various aspects such as decoration, furniture accessories, architectural decoration, bathroom accessories, lighting accessories, toys, tie clips, belt buckles, metal buckles, and high demand casting surface quality, requiring a good surface treatment. The common defect of zinc alloy die casting is surface foaming.

The reason for shrinkage is that during the solidification process of liquid metal, the liquid shrinks due to the reduction of the volume or the final solidification position.

The uneven thickness of the casting or the local overheating of the casting, resulting in slow solidification of certain parts, volume shrinkage surface depression.

Due to the porosity and shrinkage casting in the surface treatment, the hole can enter the water baking paint and after plating baking, the quality of the die casting depends on the precision of the processing equipment, the gas in the hole is heated expansion; Or the water inside the hole will change the steam volume expansion, resulting in foaming on the surface of the casting.