What is the difference between aluminum alloy die casting and aluminum alloy gravity casting
Posted by Admin
2022-04-08
Aluminum alloys are widely used in automobile manufacturing, aerospace, ships, and other fields due to their good plasticity, corrosion resistance, and lightweight. With the development of China's manufacturing industry, the demand for aluminum alloys and aluminum alloy castings is increasing, which will also promote the development of the aluminum alloy casting industry. At present, the casting methods of aluminum alloys are divided into pressure casting and gravity casting.
Aluminum alloy casting processes are roughly divided into two types: gravity casting and pressure casting.
Aluminum alloy pressure casting refers to the process in which molten metal is injected into the mold under the action of other external forces (excluding gravity). Die casting is divided into high-pressure casting and low-pressure casting.
High-pressure casting is what we usually call die casting. The aluminum liquid is poured into the pressure chamber, the mold cavity is filled at high speed through its pressure, and the aluminum liquid is solidified under pressure to form an aluminum casting.
The characteristics of aluminum alloy die castings are:
1. The surface finish of the product is good, generally reaching Ra6.3 or even Ra1.6.
2. No heat treatment.
3. The product has high airtightness, high casting strength, and surface hardness, but low elongation.
4. The mold cost is high and the service life is short.
5. High production efficiency.
6. Thin-walled parts can be produced with a small machining allowance.
Aluminum alloy gravity casting refers to the process of injecting molten aluminum into the mold under the action of the earth's gravity. Gravity casting is divided into sand casting, metal mold (steel mold) casting, lost foam casting, etc.
Now the most widely used is metal mold (steel mold) casting. The mold is made of heat-resistant alloy steel. The strength, size, and appearance of the cast aluminum casting are higher than those of other casting processes.
The molten aluminum of gravity casting is generally poured into the gate manually. It relies on the self-weight of the molten metal to fill the cavity, exhaust, cool, and open the mold to obtain the sample. The process flow is generally: molten aluminum smelting, casting filling, exhausting, cooling, mold opening, production cleaning, heat treatment, processing.