Carbonitriding is a thermochemical process in which carbon and nitrogen are simultaneously supplied to the surface of the steel piece. The process is generally carried out at 810-900°C under atmospheric control. Thinner (0.05-0.75 mm) but more abrasion-resistant surface layer than cementation is obtained and the risk of impact is lower because the process temperature is lower. It is mostly applied with thin sections and small pieces of hair. In order to harden the formed layer, watering is applied in water and oil environment. According to the required surface hardness, temper is applied on carbonitrided parts.