Several common heat treatment concept

Several common heat treatment concept

Is fire, the steel or steel heated to a critical point AC3 or ACM above the proper temperature to keep a certain time in the air cooling, pearlite organization get heat treatment process; Annealing: hypoeutectoid steel workpiece heated to above AC3 20 to 40 degrees, heat preservation after a period of time, with the slow cooling furnace (or buried in the sand or lime cooling) to 500 degrees Celsius in air cooling heat treatment process; Solid solution heat treatment: keep single-phase zone temperature alloy is heated to high temperature, the excess phase dissolves into solid solution, and then rapidly cooling, to get the supersaturated solid solution heat treatment process; Limitation: alloy after solution heat treatment or cold plastic deformation at room temperature or slightly higher than room temperature keeping, the phenomenon of its performance change with time; Various phase in the alloy solid solution treatment: fully dissolved, solid solution and improve the toughness and corrosion resistance performance, eliminate stress and softening, in order to continue processing molding; Aging treatment: in the precipitation strengthening phase temperature heating and heat preservation, make the strengthening phase precipitates out, hardening, improving strength; Quenching: the steel austenitizing with proper cooling, cooling speed after all or certain parts within the cross section within the scope of martensite and unstable organization structure change of heat treatment process; Heated to a critical point to tempering after quenching workpiece AC1 under proper temperature keeping time, method of cooling, then used to meet the requirements to obtain required by the organization and performance of heat treatment process; Steel carbonitriding: carbonitriding is to steel surface infiltration process of carbon and nitrogen at the same time. Traditionally carbonitriding is also known as cyanide.
Now as a medium temperature gas carbonitriding and low temperature gas carbonitriding (i.e., gas soft nitriding) are more widely application. Medium temperature gas carbonitriding's main purpose is to improve the steel hardness, wear resistance and fatigue strength. Low temperature gas carbonitriding with nitriding is given priority to, its main purpose is to improve the wear resistance and resistance to bite of steel; Conditioning treatment: general practice combining high temperature quenching and tempering heat treatment known as conditioning treatment. Conditioning treatment is widely used in various important structural parts, especially those who work under alternating load of connecting rod, bolts, gears and shaft, etc. Conditioning treatment after get tempered sorbite organization, its mechanical performance than the same hardness of normalizing sorbite for optimal organization. It depends on the high temperature tempering temperature and hardness and tempering stability of steel and the workpiece with the size of section, generally between HB200-350; Brazing: the two kinds of artifacts together with solder heat treatment process.