Km bearing introduces several common concepts of bearing steel heat treatment
1. Normalizing: The process of heat treatment of bearing steel with pearlitic structure is obtained by heating the steel or its parts to the critical temperature of AC3 or above for a certain period and then cooling them in the air.
2. ANNEALING: After heating the hypoeutectoid steel workpiece to 20 ° 40 ° above AC3 for a period of time, heat treatment process of bearing steel cooled in air with furnace slowly cooling (or buried in sand or lime) to below 500 deg, the process of heat treatment of bearing steel for supersaturated solid solution is obtained by fully dissolving the excess phase into the solid solution and then cooling it rapidly
4. Aging: After the alloy is heat treated or cold plastically deformed by the solid solution bearing steel, the change in performance over time when maintained at or slightly above room temperature.
5. Solid Solution Treatment: to make the various phases in the alloy fully dissolved, to strengthen the solid solution and to improve the toughness and corrosion resistance, to eliminate the stress and softening in order to continue processing and forming
6. Aging Treatment: to heat and keep the heat at the temperature where the strengthened phases are precipitated,
7. QUENCHING: The steel is austenitized and cooled at an appropriate cooling rate, bearing steel heat treatment process in which the work-piece is transformed in all or to a certain extent in the cross-section by the transformation of unstable structures such as Martensite
8. Tempering: The work-piece after quenching is heated to an appropriate temperature below the critical point AC1 for a certain period of time, the bearing steel is then cooled by a suitable method to obtain the required microstructure and properties.
9. CARBONITRIDING OF STEEL: carbonitriding is the process of simultaneous infiltration of carbon and nitrogen into the surface of the steel. Carbonitriding, also known as cyanidation, is widely used in medium temperature gas carbonitriding and low temperature gas carbonitriding (that is, gas soft nitriding) . The main purpose of medium temperature gas carbonitriding is to improve the hardness, wear resistance and fatigue strength of steel. Low temperature gas carbonitriding is mainly nitriding, its main purpose is to improve the wear resistance and bite resistance of steel. QUENCHING and tempering: It is customary to call the heat treatment of bearing steel by a combination of quenching and high temperature
10tempering quenching and tempering quenching. Quenching and tempering treatment is widely used in a variety of important structural parts, especially those working under alternating load connecting Rod, bolt, gear and shaft, etc. . After quenching and tempering treatment, the tempered sorbite is obtained, and its mechanical properties are better than that of the normalized sorbite with the same hardness. Its hardness depends on high temperature tempering temperature and is related to the tempering stability of steel and the size of the cross section of work piece, and is generally between HB200 -- 350.
11. BRAZING: Heat treatment process of bearing steel in which two workpieces are bonded together with Brazing filler metal.