While the science behind…, One of the most critical parts in the heat treatment of a metal part is the quench, or the rapid…, Heat treating 101: An introduction to heat treating procedures, The salt bath nitriding process and its safer alternative, Managing the risk of cracking in heat treating, The basics of oil quenching in heat treating. NITRIDING These processes are most commonly used on low-carbon, low-alloy steels. Fig.1 shows a schematic of the plasma nitriding process. The nitrogen ion, N+, will then diffuse into the metal surface as finely dispersed nitrides, imparting high hardness to the surface. The carbonitriding process usually takes a few hours achieve the desired results: a part with high surface hardness but with a relatively ductile core. High-density radio-frequency and direct current (RF/DC) plasma nitriding process was applied to synthesize the nitrided AISI304 microstructure and to describe the essential … Fatigue strength is increased mainly by the development of surface compressive stresses. A typical plasma nitriding process is shown in Fig.3 and the processing parameters are detailed in Table 1. A plasma nitrided part is usually ready for use directly after treatment requiring no machining, polishing or any other post-nitriding finishing operations. Material, part specs and intended uses dictate whether nitrocarburizing or carbonitriding is the best case hardening method. Together with the advantages of using only environmentally-friendly gases, plasma-based nitriding … Other, superficially cost-effective methods of enhancing surface hardness (or case hardness), involve much higher temperatures than nitriding. They improve wear resistance, seizing resistance, corrosion resistance and fatigue life of nitrided parts. Plasma Nitriding. It is an extension of conventional nitriding process, utilizing plasma discharge physic to diffuse nitrogen into the surface of a ferrous alloy. Gas nitriding is arguably the more versatile case hardening option. Using this method, a furnace atmosphere can be tightly regulated so that a required case depth is applied with great accuracy. Nitriding of steels produces less distortion and deformation than either carburizing or conventional hardening. The harden case, which is the nitriding layer is commonly known as ‘diffused case’ or ‘diffusion zone’. Plasma nitriding is a similar process to plasma carburising, but with the use of a nitrogen-hydrogen gas mixture rather than a hydrocarbon to produce the glow discharge plasma. It is an extension of conventional nitriding process, utilizing plasma discharge physic to diffuse nitrogen into the surface of a ferrous alloy. There are two forms of nitrocarburizing: austenitic and ferritic. Gas nitriding is arguably the more versatile case hardening option. If you have questions about these or other heat treating processes, be sure to get in touch or read through our heat treating guide below: Nitriding is a popular case hardening technique renowned for the qualities it delivers at relatively low process temperatures. The glow layer surrounding the job part is formed by these positive ions. Molecular nitrogen is first broken into atomic nitrogen through direct plasma dissociation. Instead of bor, nitrogen is used to improve surface properties such as hardness and wear resistance. With recent advancements in pulse plasma nitriding, a new level of precision and control is possible which results in more uniform and consistent case hardening. Plasma nitriding. Gas Nitriding Gas nitriding is a case-hardening process whereby nitrogen is introduced into the surface of a solid ferrous alloy by holding the metal at a suitable temperature in contact with a nitrogenous gas, usually ammonia. +0.4 -0.5 effective case depth During industrial metal parts fabrication, manufacturers frequently seek to harden the exterior of steel work pieces to enhance wear resistance. Heat treatment is the use of heat to modify the properties of a material, especially in metallurgy. Plasma nitriding is a smart choice whenever parts are required to have both nitrided and soft areas. Due to their shape and size, carbon atoms cannot diffuse into the part in this low-temperature process. About Nitriding. It is the latest advancement in Nitriding Technology. The Nitriding process is an established and successful means of generating a hard case on a component. Plasma nitriding, known also as ion nitriding is a form of case hardening process. 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