Wondering exactly what carbonitriding is and how it works? You’re in the right place! In this article we tell you everything. Let’s start with the definition: it is a case-hardening process similar to carburising. Unlike carburising, however, nitrogen is added: it increases the wear resistance and surface hardness of the part, creating a hardened surface layer.
Carbonitriding is a thermochemical treatment in which, as mentioned, carbon and nitrogen diffuse together into the surface of the part. Compared with carburising, the process is carried out at lower temperatures, so components are less prone to distortion. Nitrogen in particular reduces the critical quenching rate.
Related topics include electroplating and heat treatments and induction hardening, which are often part of the same treatment cycle as carbonitriding.
Carbonitriding: applications and materials
Carbonitriding is used for mass-produced mechanical components, and also for small parts that need high wear resistance. It is often applied to gears and shafts, pistons, rollers and bearings, and levers for hydraulic, pneumatic and mechanical drive systems.
Many types of steel can be carbonitrided, for example low-carbon and free-machining steels. The benefits of this process are especially clear in batch treatment of small components, which gain a hard, wear-resistant surface layer.