Aluminum Alloy Gravity Casting
Aluminum gravity casting Introduction:
The gravity casting means the part is injected by the earth’s gravity. The generalized gravity casting includes sand casting, Metal mold casting (permanent mould casting), investment casting, Lost Foam Casting, Mud casting etc. The narrow meaning of gravity casting is metal mold casting (permanent mould casting).
The permanent mold casting is modern technology that the mould made by heat resistant alloy steel.
The metal liquid generally injected into the gate by manual. Full of cavity depend on weight of liquid metal, exhaust, cool, open mould and get products.
Process flow: smelting, filling cavity, exhaust, cool, open mould, heat treatment, downstream processing.
The characteristics of the aluminum gravity casting:
1. Less casting porosity, heat treatment can be performed. The strength of the product can be improved greatly after heat treatment, better than die casting parts.
2. Product density is low, molding depend on the liquid weight, the density of the product is lower than die casting parts, its strength is slightly worse, but the elongation is higher.
3. The product surface finish is not high. Easy form similar blasting pit on the surface of casting products after cooling contraction.
4. Slow filling and low production efficiency, the production efficiency is only about a quarter compare the high pressure casting, caused the product cost is high.
5. Mould life is longer than die casting mould, and mould cost is low also.
6. Process is relatively simple.
7. Not suitable for production of thin wall parts.