Preventing Bubbles in Aluminum Alloy Die Castings
Features and inspection methods: The surface of the casting has uneven bumps or subcutaneous cavities.
Cause of occurrence:
1. If the filling degree of the metal liquid in the injection chamber is too low (controlled at 45%~70%), it is easy to generate entrainment and the initial injection speed is too high.
2. The mold pouring system is unreasonable and the exhaust is poor.
3. The melting temperature is too high, the gas content is high, and the molten liquid has not been degassed.
4. The mold temperature is too high, the retention time is not enough, the metal solidification time is not enough, the strength is not enough, the mold is opened too early, and compressed gas expands.
5. Excessive use of release agent and injection head oil.
6. The blowing time after spraying is too short, and the surface water of the mold is not blown dry.
Preventive measures:
1. Adjust the switching points for die-casting process parameters, injection speed, and high-pressure injection speed.
2. Modify the mold runner and add overflow and exhaust channels.
3. Reduce the mold temperature in the defect area, thereby reducing the pressure effect of the gas.
4. Adjusting the smelting process
5. Extend the mold retention time and adjust the blowing time after spraying.
6. Adjust the dosage of release agent and injection oil.
Product Categories : Aluminum Die Casting
