The heat treatment of castings determines - together with the chemical composition - the mechanical properties of the material. Examples of thermal treatments are stress releaving, annealing, normalising, quenching, tempering, etc.
Cast steel is always heat treated after casting. The heat treatment determines the desired microstructure and mechanical properties.
Cast iron is not heat treated as a part of the standard production process. However, low stress annealing is a common treatment for cast iron. In ADI cast iron, however, heat treatment is part of the standard production process.
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