Casting manufacturing involves pouring liquid metals into a mold where it is allowed cool and solidify into a solid piece. Once solidified a piece is removed from the mold. Then it might go some more processing and surfaces work or be utilized directly as a final piece.
Casting can be used to make complex solid and hollow parts. It is used in the automotive, construction machinery, energy equipment, and aerospace industries.
While casting is one of the oldest methods of manufacturing, advancements in technology have caused the creation of many new casting methods. Examples of thermal forming processes, include, but aren’t limited to, die casting, investment casting, sand casting, and plaster casting. Each process varies in cost, accuracy, efficiency, and material use. Choosing the best casting method based on production needs requires a thorough assessment of each method’s pros and cons.
1. Classification by Mold Characteristics
Based on mold usage characteristics, casting methods can be classified as follows:
●Expendable Mold Casting
Including sand casting, investment casting, plaster mold casting, and lost foam casting. The mold is destroyed after casting, making it suitable for complex structures or low-volume production.
●Semi-Permanent Mold Casting
Such as ceramic mold casting and graphite mold casting, where molds can be reused for a limited number of cycles.
●Permanent Mold Casting
Including metal mold casting, die casting, squeeze casting, and centrifugal casting. These molds are durable and ideal for high-volume, consistent production.
2. Classification by Driving Force and Pressure Condition
Based on the driving force used to fill the mold cavity, casting processes can be divided into:
●Gravity Casting (Free or Atmospheric Pouring)
Molten metal fills the mold cavity under the force of gravity alone.
●Externally Driven Casting
Molten metal is filled and fed under external forces such as pressure or centrifugal force, including die casting, squeeze casting, centrifugal casting, and counter-pressure casting.
3. Classification by Process Type
From a process perspective, casting methods are generally divided into two main categories:
●Sand Casting
●Special Casting Processes