Carburizing – Case Hardening

Case hardening entails the treatment of a finished component in a carburizing atmosphere at a high temperature, typically 850 – 950 ºC, which increases the carbon content at the surface of the component. The carburized layer is typically 0.1 – 1.5 mm deep but can be much deeper. Following carburizing, the component is quenched and thereby hardened. During quenching the carburized layer is transformed to martensite with hardness determined by the carbon content. Components that are case hardened have a carburized, hard surface and a much softer and tougher core. This produces a very good combination of properties: high strength, wear resistance and toughness.

Ref. Steel and its Heat Treatment – A Handbook (8.4)