Gas Nitriding requires precise control of the treatment process. Liquid Nitriding also provides the best combination of wear and corrosion protection and the shortest processing times. The process is carried out at 750-1050°F, making it faster than gas nitriding. The Ion Nitriding Process. 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. 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. Houston Unlimited, Inc. offers a salt bath nitriding process, also referred to as liquid salt bath ferritic nitrocarburizing. Salt Bath Nitriding. In many cases, it is being used as an alternative method for surface heat treatment process such as hardening, hard chrome plating with equivalent or better properties. The following table lists the typical properties produced by CST’s standard Ni-Surf process. Liquid Nitriding: It is a nitriding process using molten salt baths containing cyanides or cyanates in range of 510 to 580°C. 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. QPQ is prescribed when a smooth surface finish and maximum corrosion protection are required. Liquid nitriding uses a cyanide salt mixture in a bath. The nitrogen combines with the iron to form an iron-nitride compound layer that provides improved surface properties; e.g. Liquid Nitriding Salt bath nitriding / liquid nitriding is a subcritical surface enhancement process holding the longest track record of success over any case hardening technology. This is accomplished by heating the metal to 520°C/970°F and introducing nitrogen-rich ammonia. Liquid Nitriding achieves results by means of a chemical reaction (at temperatures lower than conventional heat treatment) that leads to the formation of a hard nitride compound on the surface of the component. Besides, the process has few advantages, quick heating of the work piece being the only one worth mentioning. PVD coatings involve the deposition of thin (2-10 microns; 0.0001" – 0.0004") films on the surface of tools and components. Nitriding, or, nitrocarburizing, can be accomplished using four different media: 1) Liquid; 2) Gas; 3) Plasma; and 4) Fluidized Bed. This form of heat treating is well documented in showing consistent case depths throughout the entire surface area of … We are franchise of M/s Hydromacnique et Frottment, France, since 1992 for Liquid Nitriding Process (Sursulf). Parts up to 57 in. The process infuses nitrogen more deeply into the item; however, it also infuses additional carbon. resistance to wear, friction, corrosion, and fatigue. Liquid nitriding is used where low case-depth is required and is then cheaper. Liquid nitriding is a subcritical surface enhancement process with one of the longest track records of success of any case hardening technology. The gas nitriding temperature is 520°C, lower than the 550°C to 570°C temperature required for liquid nitriding. All are actually nitrocarburizing processes that use molten salts as a source of nitrogen (+ some carbon). We are The nitrogen infuses to a deeper level with liquid nitriding than it does with gas nitriding. When the nitrogen ions bombard the part they heat up the … The ion nitriding process is carried out in a vacuum vessel where a high-voltage electrical charge forms plasma, causing nitrogen ions to accelerate and impinge on the metal. Process Selection and Quality Control. As Liquid Nitriding is a manual process, it isn’t possible to control the white layer thickness. It remains a popular case … It’s time for the main event – liquid nitriding vs gas nitriding. Chromium has a high affinity for nitrogen and slows diffusion, thereby limiting the achievable case depth. This is done by immersing the parts in specially formulated 'salts' between 400°C - 425°C (750°F -800°F); (2) POLISHING: to improve surface finish and (3) RE-OXIDATION: to recover the oxide layer thickness that may have been lost during the polishing step. It is heavily utilized on automotive components like crankshafts and gears. Salt baths presents dangers to the environment and to the personal safety of the operators. 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