Carburizing is a thermochemical diffusion process which adds carbon to the surface of a low carbon steel. The carbon diffusion depth and the related effective case depth can vary from 0.1 to 6mm.

The total process is applied in three phases:

• Carburizing is A thermochemical process in a chamber furnace with integrated quench to enrich the surface in a carbonaceous encironment in a temperature range of 880 to 980 degrees.
• Hardening is achieved after quenching eithger in oil, polymer/water solution.
• A tempering operation follows. Tempering temperature and time at heat depend on product requirement and application. THe tempering process nubunuses peak stresses and reduces crack initation.

The following information is required for performing case hardening:

Material

Case depth in mm (CHD)

Partly case hardening possible

Insulation requirements, where relevant (e.g. in the form of a workpiece drawing indicating sections that must not undergo hardening)

The purpose of case hardening is to give the surface layer of steel workpieces and tools a significantly greater hardness and to improve their mechanical properties. Case hardened components and tools are characterized by their increased resistance to wear, tough core, and increased bending fatigue strength. Such characteristics are of particular importance in gear components.

Case hardening steels are construction steels with a relatively low carbon content, whose surface layer is generally carburized or carbonitrided prior to hardening. The carbon content of case hardening steels is generally below that of hardened and tempered steels, i.e. less than 0.25%.