Casting vs Forging – Difference and Comparison

What is Casting?

Casting is a process in which we pour molten metal into a mold and allow it to cool so that it hardens and takes the shape of the mold. The cemented part is called casting, which is taken from the mold to complete the process. Mainly casting material is metal that hardens after combining two or more components, e.g., plaster of Paris, clay, epoxy, and concrete. In metal casting, we have two categories, i.e., process with reusable and expendable molds. There is an isotropic structure in casting.

The three main types of casting are dying casting, investment casting, and sand casting. This process was developed over 5500 years ago. We find its trace root in both china and Egypt. It is also said that in Mesopotamia, 3200 B.C.E., the earliest casting was a copper frog. Beeswax was used in this process.

Mainly casting is used to create complex shapes that are difficult to create or that will not be economical by using any other method. Casting is the cheapest process as compared to other manufacturing processes. It creates a perfect object. Casting is widely used in transport, jewelry making, heavy equipment, machine tools, plant machinery, household, etc. In casting, the size of the object does not matter. It is an excellent economical option for creating complex structures.

What is Forging?

Forging is a process in which metals are placed under solid compressive forces to change their shape and form. This procedure includes hammering, rolling, and pressing to give the metal the desired shape. Forging is used in the manufacturing of various metals and machinery. There are numerous methods used in forging. Some of them include hot forging and cold forging.

The divisions, as mentioned above, are made based on the temperature of the metal being worked on. The cold forging procedure is done at room temperature, where the metal is compressed between two dies until it adopts a shape. On the other hand, hot forging is carried out by placing the metal under extremely high temperatures of several hundred degrees.

Cold forging has an advantage over hot forging as it is cost-efficient. Still, this process only produces simple shapes and forms. Furthermore, hot forging provides easy customization of metal. Nonetheless, this procedure demands additional costs. The manufacturing of all sorts of metals involves the use of this technique. Its applications include the construction of heavy machinery for various industries, aircraft and missiles, automotive, electric power generation, and aircraft engines.

Difference Between Casting and Forging

  1. Casting involves the use of cavities and hollow spaces for shape, whereas in forging, such techniques are not used.
  2. Casting involves the use of metals low in strength, whereas forging always has strong metals involved.
  3. Casting produces complex shapes and patterns as a result, whereas forging produces relatively simpler shapes.
  4. Casting is regarded as an inexpensive process, whereas forging is an expensive process in many aspects.
  5. Casting does have primary and secondary operations for refining and finishing, whereas forging seldom has them.

Comparison Between Casting and Forging

Parameters of ComparisonCastingForging
Material SelectionAlloys Selection is SparseSuitable for Almost All Metals
Tensile StrengthLow Tensile StrengthHigh Tensile Strength
End ProductsComplex Patterns & ShapesSimple Textures & Designs
Secondary OperationsRefining & FinishingRarely Involved