1, electromagnetic heating, electromagnetic heating is an alternating magnetic field generated by electronic circuit board components. When an iron-containing container is placed on it, alternating magnetic lines are cut on the surface of the container, and alternating current (i.e. eddy current) is generated in the metal part at the bottom of the container. The eddy current makes the iron atoms at the bottom of the container move irregularly at high speed, and the atoms collide with each other to generate heat energy. So as to achieve the effect of heating articles.
2, infrared heating, infrared heat transfer form is radiation heat transfer, energy is transmitted by electromagnetic waves. When far infrared rays shine on a heated object, some rays are reflected back and some are penetrated. When the emitted far infrared wavelength is consistent with the absorption wavelength of the heated object, the heated object absorbs the far infrared. At this time, the molecules and atoms inside the object vibrate and rotate strongly, which makes the temperature of the object rise, thus achieving the purpose of heating.
3. Resistance heating, which uses current to release heat through an electric heater to heat the blank. Common resistance wire heating, ceramic heater, resistance coil heating and quartz tube heating all belong to resistance heating in principle.
Extended data:
1, resistance heater heating is the most primitive, so the thermal efficiency is also the worst, usually the thermal efficiency is only about 70%, and a lot of heat energy is emitted into the air.
2. Infrared heating method is better than resistance, but there is still a lot of heat emitted into the air, but it is not infrared itself that emits heat into the air, but the heated object that emits heat into the air.
3. When the electromagnetic heater works, the heated object is wrapped by the insulating layer, and then the magnetic field directly heats the object itself through the insulating layer, so the thermal efficiency is the highest, with almost no heat energy loss, and its thermal efficiency exceeds 95%.
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