Ten major defects of die casting

With the development of technology, die casting has the advantages of high dimensional accuracy, good mechanical properties and high production efficiency. It has broad application prospects in automobiles, motorcycles, internal combustion engines, electronics, instrumentation, aerospace and other fields. However, during the production process, the molding of die castings is affected by many factors. For example, the aluminum alloy solution is easily involved in gas during the flow process, and the temperature distribution during the casting process is unbalanced, which can easily lead to many defects in the castings. The following summarizes the top ten common defects in die casting.

1. Casting parts have flow marks and patterns

There are stripes on the surface of the casting parts that are consistent with the flow direction of the molten metal, and there are obviously non-directional lines that are different in color from the metal matrix.

2.Cracks appear in casting parts

There are raised or depressed marks on the surface of the die-casting parts like hairlines, which continue to expand and extend as the number of die-castings increases.

The surface of the die-casting parts has obvious, irregular, sunken linear lines (both penetrating and non-penetrating), which are small and narrow in shape. Sometimes the intersection edges are smooth, and there is a possibility of disconnection under the action of external force.

4. Shrinkage (dent) in casting parts

A relatively thick aluminum casting with smooth indentations (like a dish) on most surfaces.

Marks left by the contact between the surface of the casting and the surface of the die-casting cavity or step marks on the surface of the casting.

Small flakes and the base part of metal or non-metal are welded to the metal, and the small flakes peel off under the action of external force. Some of the surfaces of the peeled castings are shiny and some are dark gray.

There are obvious layers of metal in parts of the casting.

The die casting surface has rough surfaces in certain locations.

There are pits or ridges in some die-casting parts.

There are pits or ridges in some die-casting parts.