Introduction: ‘Forging’ vs ‘casting’

The difference between ‘forging’ and ‘casting’

Casting is a process of forming metal by pouring molten metal into a mold. Forging uses hammer, with which metal is beaten into shape. The production process of a katana (Japanese sword) is typical forging, and another example from everyday life is a coin.

Another feature distinguishing forging from casting is such that metal is strengthened as it is being shaped into a product. Beating a metal increases its strength and eliminates pinholes in it, resulting in products with high strength.

Making metal (steel and such) harder and stronger by beating it on an anvil is a millenia-old technique. Repeated beating and bending changes the metal’s molecular arrangement, making it more complex, which is the key of the hardening technique. Forging is, however, more than just beating. High quality forging requires the expertise to control various conditions, such as the purity of metal, the heating temperature, the accuracy of the mold, pressure loading, and more.