Heat Treatment Chemicals
Salt bath heat-treating methods are uniform, quick, efficient, economical, and environmentally responsible.Salt baths are used in a wide variety of commercial heat-treating operations including neutral hardening, liquid carburizing, liquid nitriding, austempering, martempering, and tempering applications. Salt bath equipment is well adapted to heat treatment of ferrous and nonferrous alloys.Parts that are heated in molten salt baths are heated by conduction; the molten salt bath provides a ready source of heat as required.
Tempering is a process primarily use to increase ductility and toughness, but also to increase the grain size of the matrix. Steels are tempered by reheating after hardening to obtain specific values of mechanical properties and also to relieve quenching stresses and to ensure stability.The purpose is to delay the cooling just above the martensitic transformation for a length of time to equalize the temperature throughout the piece. This will minimize the distortion, cracking, and residual stress.Salt bath is Rapid, uniform heating; low to medium volume; should not be used for parts whose configurations make them hard to clean
Austempering in Heat Treatment. It is the isothermal transformation of a ferrous alloy at a temperature below that of pearlite formation and above that of martensite formation.
Quenching for Heat Treatment refers to the process of rapidly cooling metal parts from the austenitizing or solution treating temperature which is done by water,oil, polymer and brine solutions.
The normalizing operation consists of passing the sheet or strip through an open, continuous furnace where the material is heated to a temperature approximately 55 to 85 °C above its upper transformation temperature,845 to 900 °C in obtaining complete solution of the original structure with the formation of austenite and then air cooling the material to room temperature.
Annealing It is a generic term denoting a treatment that consists of heating to and holding at a suitable temperature followed by cooling at an appropriate rate, primarily for the softening of metallic materials
Liquid carburizing is a process used for case hardening steel and iron parts. The parts are held at a temperature above Ac1 in a molten salt that will introduce carbon and nitrogen, or carbon alone, into the metal. Diffusion of the carbon from the surface toward the interior produces a case which can be hardened, usually by fast quenching from the bath.Carbon diffuses from the bath into the metal and produces a case comparable with one resulting from gas carburizing in an atmosphere containing some ammonia.
Liquid Nitriding processes are used primarily to improve wear resistance of surfaces and to increase the endurance limit in fatigue. antigalling properties, increased fatigue resistance, and less distortion than other case-hardening processes employing through heating at higher temperatures
Alkalian Cleaning is a commonly used method for removing a wide variety of soils from the surface of metals. The main chemical methods of soil removal by an alkaline cleaner are saponification,displacement,emulsification and dispersion, and metal oxide dissolution.
Alkaline cleaners have three major types of components: builders, which make up the bulk of the cleaner; organic or inorganic additives, which promote better cleaning or affect the rate of metal oxide dissolution of the surface; and surfactants.
A mineral acid, organic acid, and acid salt, in combination with a wetting agent and detergent, is used to remove oxide, shop soil, oil, grease, and other contaminants from metal surfaces, with or without the application of heat.
The process used in electroplating is called electrodeposition in which electrical current to reduce dissolved metal cations so that they form a coherent metal coating on an electrode.
Nickel plating is used extensively for engineering, electroforming and modern decorative nickel plating solutions contain organic additives that modify the electro crystallization process so that mirror-bright, highly-leveled nickel coatings are deposited directly from solution
Chrome Plating :Hard chromium plating is produced by electrodeposition from a solution containing chromic acid (CrO3) and a catalytic anion in proper proportion.
Galvanizing Zinc and Zinc Plating
Zinc Commercial zinc plating is accomplished by a number of distinctively different systems: cyanide baths, alkaline noncyanide baths, and acid chloride baths while galvanized zinc is molten Zinc process for coating.