nitrureerimine

Nitrureerimine, or nitriding in English, is a heat-treatment process in which nitrogen is introduced into the surface of a metal, most commonly steel, to form a hard nitride-containing case. The primary aim is to raise surface hardness and wear resistance while preserving the ductility and toughness of the underlying material. The process typically occurs at moderate temperatures and does not require quenching, helping to minimize distortion.

The main methods are gas nitriding, plasma (ion) nitriding, and liquid (salt-bath) nitriding. Gas nitriding uses an ammonia-containing atmosphere at roughly 500 to 570 °C, producing nitrogen-rich metal compounds such as epsilon-Fe2-3N and gamma'-Fe4N. Case depths generally range from about 0.1 to 0.6 millimeters, though deeper cases are possible with longer cycles. Plasma nitriding employs a glow discharge in a nitrogen-containing gas at similar or slightly lower temperatures, offering finer control and good uniformity for complex shapes; thinner, harder cases are typical but can be produced with controlled parameters. Liquid nitriding uses molten salt baths at around 500 to 550 °C and can provide uniform surfaces with relatively low distortion.

Benefits of nitrureerimine include increased surface hardness, improved wear and fatigue resistance, and, for some steel grades, enhanced corrosion resistance in specific environments. Limitations include higher processing costs and the need for proper alloy selection and process control. The resulting nitrided layer is hard and brittle near the surface, so post-treatment tempering or controlled cooling is sometimes employed to balance properties.

Applications span gears, crankshafts, camshafts, valves, bearings, and cutting tools, with widespread use in automotive, tooling, and aerospace industries.