Die Casting Alloy and Die Steel Affinity

- Jun 21, 2018 -

The greater the affinity of the die-cast alloy and the die steel, the easier it is to fuse and bond together. After the die-casting alloy is adhered to the wall, a large release resistance will be generated, and the casting will be pulled when it is released. Visual observation of the surface of the casting's mucous membranes, such as surface roughness, peeling, or lack of material, was observed (Note: to be distinguished from carbon deposition). In the case of severe bonding, the castings were torn and damaged.

Visually adhering a layer of die-casting alloy to the surface of the cavity of the mold, and the color is whitened. After the die-casting alloy liquid is sprayed or flows through the impact wall or the core, the temperature of the wall or the core is increased, and at the high temperature, the alloy liquid and the mold steel of the wall are melt-welded to generate mutual adhesion. The higher the temperature of the alloy liquid, the higher the injection speed, the higher the mold temperature, and the lower the hardness of the mold, the higher the affinity of the aluminum alloy liquid to the mold steel, and the easier the melt and weld adhesion. The surface of the die with the die-casting alloy adhered to the surface of the casting when the casting was demoulded. The surface of the casting was torn and tearing, and the surface of the casting was torn and the surface of the casting showed a tensile die.

The higher the filling speed of the die casting alloy liquid in the runner, the more violent the metal flow impacts the die wall. The molten metal directly impacts the core or the wall, and the impact force is converted into heat energy. Not only the temperature of the alloy liquid will rise, but also the mold temperature at the impacted part will increase a lot, greatly increasing the affinity of the aluminum alloy liquid and the mold steel. Therefore, at the runners in the mold, the parts that are subjected to the high-speed impact of the alloy fluid are most likely to exhibit sticking. If the impact is on one side of the fixed mold, the tightening force of the casting on the side of the fixed mold is increased.

The hardness of the mold is insufficient, and the surface of the mold at the time of mold release will be deformed by the die casting alloy, or the mold core will be bent and deformed, thereby increasing the mold release resistance of the mold.

Improper use of mold materials, when the mold temperature is high, the die-cast alloy can easily adhere to the mold surface.