Heat treatment and thermal control is important in creating the required properties of forged products. This allows relief of internal stresses and grain structure control, which provide improved material properties.
Now that thermography is a commonplace industrial technique, today’s invention is to use this to help control the local properties within forged components. This could be achieved by directing a jet of coolant gas to provide computer-controlled, spot cooling of the hot regions in a forged workpiece (it doesn’t have to use air, if you are concerned about oxidation).
This would allow greater certainty about the local rates of cooling and thus help to form components with varying properties in different regions. A bearing surface could be specially hardened, whilst leaving a defined level of elasticity in the shaft section of a single, multiproperty forging, for example.
This would certainly require very high speed, very narrow gas jets in order to achieve refined cooling within the body of a thick-section component.