Both processes case-harden items but consider the following differences before choosing a method. This is a thermo-chemical reaction where primarily nitrogen and other elements are diffused into the … Liquid-Equivalent Stainless Steel Nitriding. The life span of the product increases due to this process. Liquid Nitriding is often referred to as a heat treatment; but, this is technically incorrect. Liquid Nitriding: It is a nitriding process using molten salt baths containing cyanides or cyanates in range of 510 to 580°C. The process infuses nitrogen more deeply into the item; however, it also infuses additional carbon. Salt bath nitriding is a thermochemical process in which nitrogen and carbon are diffused simultaneously into the surface of the material. Process Selection and Quality Control. Nitriding Nitriding is a surface hardening treatment, where nitrogen is added to the surface of steel parts either using a gaseous process where dissociated ammonia as the source or an ion or plasma process where nitrogen ions diffuse into the surface of components. A composition for nitrocarburizing stainless steel parts and a method for producing a nitride or hard case on such parts using the composition, are provided. Besides, the process has few advantages, quick heating of the work piece being the only one worth mentioning. However, it is not nearly as dangerous as the highly toxic cyanide salts used in the liquid method. Liquid nitriding is used where low case-depth is required and is then cheaper. Liquid Nitriding process involves enrichment of the Steel Surface basically with Nitrogen and very small amount of Carbon at a specified temperature range, by diffusion from Cyanide-free molten salt bath. The composition includes alkali metal cyanate and alkali metal carbonate, wherein the cyanate ion is present in a weight percentage of greater than 45% and less than 55.2%. Nitriding provides only nitrogen to the surface of the work piece, and is normally accomplished in gas or plasma atmospheres, using much longer cycles to achieve deep diffusion depth. The Liquid Nitrocarburizing will not be suitable as the layer thickness of 10 to 15 microns compound zone will not take up abrasive wear effectively. MELONITE®, TUFFTRIDE® and ARCOR® are all liquid nitrocarburizing processes, and trademarks of the HEF Group (TS USA and HEF USA are US subsidiaries). Liquid Nitriding Services This is a non-pollutive salt bath Ferritic Nitro Carburizing Process and is operating at the temperature of 565 ± 5 ° c. Our liquid niriding process provides an effective answer to the problems of wear, fatigue, scuffing and corrosion encounter with steel and iron components used in engineering industries. When steel parts are placed into a preheated liquid salt, there is sufficient energy localized near the surface due to differences in chemical potential that then allows nitrogen and carbon species to diffuse from the salt into the steel substrate. QPQ is prescribed when a smooth surface finish and maximum corrosion protection are required. However, liquid is considered the benchmark for uniformity, consistency, and flexibility. PVD coatings involve the deposition of thin (2-10 microns; 0.0001" – 0.0004") films on the surface of tools and components. This specialty process improves on the more commonly used salt-bath (liquid) nitriding method by offering deeper case depths and higher quality case hardening The second challenge with stainless steels is the high amount of Chromium. The liquid nitriding process has several proprietary modifications and is applied to a wide variety of carbon steels, low-alloy steels, tool steels, stainless steels, and cast irons. Nitriding and Oxidation Surface increase the excellent corrosion resistance. Liquid Nitriding Offers a Different Approach to Case-Hardening In this process, the item is heated to the desired temperature (550°C/1,020°F to 570°C/1,060°F) and then immersed in liquid cyanide salt. The method features the transfer via diffusion of carbon and nitrogen from the molten salt to the surface of a steel part. Parts up to 57 in. MELONITE® and TUFTRIDE® are identical processes – the former term is prevalent in North America, and the latter term in the rest of the world. Gas Nitriding is a low temperature case hardening process that is ideal for producing hardened surfaces on pre-heat treated alloy steels such as 4140 and 4340, pre-heat treated tool steels such as H13, and specialty grades such as Nitralloy 135M. Liquid nitriding uses a cyanide salt mixture in a bath. Liquid nitriding is a subcritical surface enhancement process with one of the longest track records of success of any case hardening technology. QPQ Liquid Nitriding (also known as salt bath nitriding) is a process for producing a thin, high-hardness case that is wear and corrosion resistant, with little or no distortion of the part during processing. Different trade names are used due to differences in the chemistry of the nitriding chemicals and the secondary processing steps. Nitriding Nitriding is a surface hardening process in which nitrogen present in the atmosphere in the nascent form of N1 diffuses into the surface of the steel and forms nitrides with certain critical elements such as chromium, molybdenum, vanadium, aluminum, tungsten and iron. HEF bushings are recognized worldwide for their excellent frictional and anti-seizure properties, and ability to withstand high loads. Salt Bath Nitriding. The process is carried out at 750-1050°F, making it faster than gas nitriding. 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