There exits shrinkage in surface of die cast mold. I will introduce you in details as followings:
Shrinkage hole is the surface of the die cast mold surface or the existence of a surface rough hole. There also are a lot of small shrinkage hole, that is, shrinkage. Shrinkage often occurs in the castings near the runner, riser root, thick parts, the thickness of the wall junction and has a large plane of the thickness.
- The temperature control of die cast mold does not meet the directional solidification requirements.
- The choice of paint is improper, different parts of the coating layer thickness control is not good.
- The casting mold in the position of improper design.
- Pouring riser design failed to achieve the full complement from the role.
- Pouring temperature is too low or too high.
- Improving the abrasive temperature.
- Adjusting the thickness of the coating layer and uniforming spray paint, coating off and the coating can not be formed when the local accumulation of paint phenomenon.
- The die cast mold is local heated or insulation with local insulation materials.
- Hot section at the copper block, while chilling the local.
- The mold design heat sink, or through water and other local areas to speed up the cooling rate.
- With removable chi-chill cold block, in turn placed in the cavity, to avoid continuous cooling chill itself when the production is not sufficient.
- The mold riser design pressure device.
- Pouring system design to be accurate, select the appropriate pouring temperature.