Heat treatment furnace is an important process to improve the comprehensive properties of metal workpieces. Heat treatment is mainly divided into three stages: heating, heat preservation and cooling. Some of the heat treatment processes have no heat preservation but only heating and cooling. Heating is one of the most important processes in heat treatment.
There are many heating methods for heat treatment of metals. First, charcoal and coal are used as heat sources, and then liquid and gas fuels are used. The application of electricity makes heating easy to control and free of environmental pollution. These heat sources can be heated directly or indirectly by molten salt or metal or even floating particles.
When the metal is heated, the workpiece is exposed to air and often oxidized and decarburized (that is, the carbon content on the surface of iron and steel parts is reduced), which has a negative effect on the surface properties of the parts after heat treatment. Therefore, metals should usually be heated in controllable or protective atmosphere, molten salt and vacuum, or protected by coating or packaging.
Cooling is also an indispensable step in the process of heat treatment. The cooling method is different according to the process, and the cooling rate is mainly controlled. The cooling rate of general annealing is the slowest, the cooling rate of normalizing is faster, and the cooling rate of quenching is faster. But different kinds of steel have different requirements, for example, air-hardened steel can be hardened at the same cooling rate as normalizing.
Overseas manager: Tom Wang
Email:tom@foreverfurnace.com
Phone: 0086-13303078975(whatsapp, wechat,line)
Specialist of bar heat treatment furnace in China; Glad to be your business partner in induction heating field.
Post time: 04-28-2019