Forged bars and components are typically stronger than cast ones because forging refines the grain structure. A cast part cools slowly and forms coarse grains, which give lower strength; forging breaks those grains down into a finer structure that carries a higher yield strength.
Grain size controls strength
The mechanical properties of a metal are heavily influenced by its internal microstructure. When molten metal solidifies it forms a crystalline structure, and it is very difficult to create a single crystal. The stainless steels, nickel alloys and copper alloys we supply are all made up of a huge number of individual crystals, or grains.
The boundaries between these grains slow down deformation when the metal is loaded. A metal with a fine grain size therefore has a higher yield strength than one with a coarse grain size.
Why forging out-performs casting
A cast component cools very slowly from the molten state, which encourages large grains and a lower strength. When a cast ingot is forged, the reduction in section breaks down the individual grains and refines their size.
The result is a far finer grain structure, with increased strength and more consistent properties in different axes. This is why forged bars and components generally out-perform cast ones.