plasmacarbureren

Plasmacarbureren, also known as plasma carburizing, is a thermochemical surface treatment used to increase the surface hardness and wear resistance of ferrous alloys. In this process, a carbon-rich surface layer is formed by diffusion of carbon into the metal from a gas kept in a low-pressure plasma environment. The plasma ionizes the gas, typically hydrocarbon gases such as methane or propane, enabling carbon-bearing species to reach the surface and diffuse inward at temperatures lower than those used in conventional carburizing.

The process is performed in a vacuum or low-pressure chamber equipped with electrodes to generate a glow discharge. Workpieces are cleaned, placed in the chamber, and exposed to controlled gas mixtures and temperatures, usually in the range of 370–520°C, for times ranging from a few hours to several days depending on the desired case depth. The diffusion layer is followed by a quench and tempering if required.

Plasmacarbureren yields a hard, diffusion-built case while preserving a tougher core. Typical case depths range from fractions of a millimeter to about 1 millimeter, and surface hardness can reach around 60–62 HRC, depending on alloy and post-treatment. The process offers uniform coverage on complex geometries, low distortion, and reduced environmental impact compared with traditional gas carburizing. It is commonly applied to low- to medium-carbon steels and alloy steels used for gears, bearings, camshafts, crankshafts, and cutting tools.

Quality control relies on hardness testing and case-depth profiling, as well as microstructural analysis to ensure the desired carbon profile and the absence of excessive retained austenite. Post-treatment tempering is often used to achieve target mechanical properties.