Forgings Manufacturing

The advantages of forging in manufacturing stem from what’s actually happening to the particle structure of the metal itself, and the consistency. In cast manufacturing, molten metal is poured into a shape – expelling the air previously occupying that space.

While casting is often the most cost effective way to create a part, and is suitable for many applications, the grain structure and improved purity of a forged part is why they’re suitable for high stress, critical applications.

Forging is done by heating raw steel to around 1200℃, then shaping it using forging machines. This shaping is generally done by pressing or hammering, i.e. applying great force to deform the raw material into the shape of the desired part.

In simple terms, when a part is created through forging methods, the internal grain structure follows the shape of the part – similar to a tree branch. In doing so, the grain flow is continuous and provides directional strength properties in the critical regions where the material undergoes deformation.

In the case of a casting, for example, the steel is melted in liquid form and poured into a mould of the desired shape. When the metal solidifies, the internal grain structure is randomly distributed, because the metal was fully melted in order to be poured into the mould.

This means that the grain flow has been disturbed, and the advantage of continuous grain flow has been lost. The grain flow properties of forgings are vital in fatigue loading conditions of safety-critical products. No other process can impart these directional properties like forging does.