How die forgings compare to castings

How die forgings compare to castings
Forgings are stronger. Casting cannot obtain the strengthening effects of hot and cold working. Forging surpasses casting in predictable strength properties–producing superior strength that is assured, part to part. Forging refines defects from cast ingots or continuous cast bar. A casting has neither grain flow nor directional strength and the process cannot prevent formation of certain metallurgical defects. Pre-working forge stock produces a grain flow oriented in directions requiring maximum strength. Dendritic structures, alloy segregations, porosity, voids, inclusions, and like imperfections are refined in forging. Thus finishing operations, such as machining, do not expose voids because there aren’t any. Also, coating operations, such as plating or painting, are straightforward due to a good surface, which needs very little preparation.
Reliable standard and custom forgings are manufactured without the added costs for tighter process controls and inspection that are required for casting. Castings require close control of melting and cooling processes because alloy segregation may occur. Forging’s flexible production adapts to demand. Some castings, such as special performance castings, require expensive materials and process controls, and longer lead times. Open-die and ring rolling are examples of forging processes that adapt to various production run lengths and enable shortened lead times. So forgings are more cost effective than castings.