What is the difference between lost foam casting and pressure casting?

Lost foam casting (Lost Foam Casting) and pressure casting (Pressure Casting, referred to as die casting) are two different casting processes. They have significant differences in principles, characteristics, applications, advantages and disadvantages, etc. The following is a detailed analysis of the differences between these two casting processes:

The principles are different

Lost foam casting: Foam models similar in size and shape to the casting are bonded and assembled into model clusters. After they are painted with refractory paint and dried, they are buried in dry quartz sand and vibrated to shape. They are cast under negative pressure to vaporize the model. The liquid metal occupies the position of the model, solidifies and cools to form the casting. This process is also called full mold casting or EPC casting (Expendable Pattern Cast Process).

Pressure casting: A casting method in which liquid or semi-solid metal or alloy is filled into the cavity of a die-casting mold at a high speed under high pressure, and the metal or alloy is solidified under pressure to form a casting. The commonly used pressure during die casting is 4-500MPa, and the metal filling speed is 0.5-120m/s.

Application areas

Lost foam casting: widely used in automobiles, aerospace, machinery manufacturing and other fields, especially suitable for castings with complex shapes that are difficult to manufacture using traditional casting methods.

Pressure casting: Mainly used in mass production of non-ferrous alloy castings. For example, aluminum alloy die castings play an important role in the automobile and tractor manufacturing industries, followed by instrument manufacturing and electronic instrument industries.

Summary of advantages and disadvantages

Advantages of lost foam casting:

Castings have high dimensional accuracy and good surface quality.

It has great freedom of design and can produce castings with complex shapes.

Green and clean production, high material utilization rate.

It has a high degree of automation and can achieve large-scale and mass production.

Disadvantages of lost foam casting:

The initial equipment investment is relatively large.

The quality requirements for foam plastic models and coatings are relatively high.

Advantages of pressure casting:

The production efficiency is high and it is easy to realize mechanization and automation.

Castings have high dimensional accuracy and small surface roughness values.

Parts can be embedded and cast to simplify the manufacturing process.

Disadvantages of pressure casting:

Castings are prone to defects such as pores and cracks, and usually cannot be heat treated.

The structure of the die-casting mold is complex, the manufacturing cycle is long, and the cost is high.

The die-casting machine has high cost and investment. It is limited by the clamping force and mold size of the die-casting machine, and is not suitable for the production of large-scale die-casting parts.

In summary, there are obvious differences between lost foam casting and pressure casting in terms of principles, characteristics, applications, advantages and disadvantages. When selecting a casting process, comprehensive considerations should be made based on factors such as the requirements of the specific casting, production conditions, and economy.