If the copper sleeve and zinc-based alloy sleeve have a high mold temperature, the metal filling ability can be improved, and the preheating mold method is usually used to ensure the filling of thin-walled castings.
The thermal conductivity of the coating is small, the thickness is large, the heat dissipation of the alloy liquid is slow, and the filling capacity is also improved.
The mold material has a certain gas production capacity, forming an air mold between the metal and the mold, which not only reduces the flow resistance, but also produces a heat-resistant layer, thereby improving the filling capacity of the copper sleeve alloy.
The filling pressure is high, the pouring position is suitable, the top-spray pouring system is adopted, the cross-section is large, the resistance is small, etc., and the casting process conditions are favorable for filling.
Increasing the pouring temperature and casting speed of the copper sleeve can significantly improve the filling capacity of the copper alloy. For alloys with low fluidity and thin-walled castings, the above method is usually used to ensure complete filling. However, when the pouring temperature
A large amount of gas and severe oxidation, so the grain of the casting is rough, and it is easy to cause casting defects, such as shrinkage, shrinkage, heat, and sand sticking. Pouring too fast will easily cause defects such as sand washing and sand swelling, so it is not recommended
Pouring speed increased too high.
If the cast copper sleeve has a large modulus, it is easy to fill. The casting structure is complex and difficult to fill.
Finally, in order to improve the filling capacity of copper alloys, the measures that should be taken are: correct selection of alloy components, strict smelting process, such as refining, deterioration, etc.; modeling materials and coatings, low heat storage coefficient; temperature; strengthening copper
Capacity; For thin-walled complex castings, the casting temperature and casting weight should be appropriately increased, the pouring position suitable for the filler should be selected, the filling head should be increased, and the resistance of the casting coefficient should be reduced.