Cast aluminum generally refers to aluminum castings manufactured by casting process, and die-casting aluminum refers to aluminum castings manufactured by high-pressure die-casting. The difference between the two is mainly the difference of casting process.
Casting processes generally include sand casting, dewaxing casting, gravity casting, low-pressure casting, ceramic mold casting, gypsum mold casting and other casting processes.
Die casting process is a kind of high pressure die casting, which is produced by cold chamber die casting machine.
The cast aluminum grades used in the two processes are also different.
In China’s national standard GB, ZL represents the cast aluminum alloy grade and YL represents the cast aluminum alloy grade.
Generally, cast aluminum castings can be strengthened by heat treatment. T6 heat treatment is generally adopted, while die castings are not suitable for T6 heat treatment because a large amount of gas is densely distributed inside.
(The reason is that the temperature of T6 heat treatment is very high, which is about 15-20 degrees lower than the melting point of aluminum alloy.
At this time, the gas in the die casting will expand and be forced out of the casting surface, which will make the surface of the die casting dense.
Due to the dot protrusion after the gas runs out, the appearance of the casting is seriously damaged and can not be used).
Aluminum alloy gravity casting and aluminum alloy low-pressure casting belong to the metal mold casting process.
Both are used to produce aluminum castings. The molds belong to metal mold. Hot work die steel (such as H13) is used to make molds.
Aluminum alloy gravity casting and aluminum alloy low-pressure casting process can produce the same brand of cast aluminum alloy.
The pouring temperature and mold opening time of molten aluminum are similar, and the compactness, strength and other mechanical properties of aluminum castings are similar.
There are still differences between aluminum alloy gravity casting and aluminum alloy low-pressure casting in forming principle, aluminum casting structure, labor intensity, batch number, development time, etc., as shown in the figure below:
|Forming principle||Aluminum casting structure||labour intensity||Minimum batch||Development time||Mold cost|
|Aluminum alloy gravity casting||Using gravity||Complex and diverse||high||100||short||less|
|Aluminum alloy low pressure casting||Using air pressure||single||commonly||500||long||Higher|
According to the comparison of the above figure, aluminum alloy gravity casting is more suitable for the production of products with multiple varieties, small batches, short development cycle and high quality requirements, while aluminum alloy low-pressure casting is suitable for the production of products with large batches, thin wall thickness and structure suitable for aluminum alloy low-pressure casting process.
The long development cycle is conducive to the improvement of production technology in the production process.
The typical product produced by aluminum alloy low-pressure casting process is automobile wheel rim.
The structure of this aluminum casting is very suitable for the structural characteristics of low-pressure casting process, and the production volume is very large, so there is enough time to improve the production technology.
The typical products produced by the aluminum alloy gravity casting process are industrial robot castings.
These aluminum castings have small production batch, high product quality requirements and short development cycle.
It is necessary to produce high-quality aluminum castings without any pores and sand holes in a very short time.