Ever wonder how induction heating worked? Me too… Penguin Labs has an informative article about some of their experiments.
“Induction cookers, furnaces, stoves and all that jazz are now widely used. You put your metal saucepan on top of an innocent looking glass plate and it magically heats your food with no flame and almost no waste heat.
They are able to heat certain metals up to their melting points, and that is very hot, obviously…
How they work?
When an alternating electric current is passed through a coil, the coil creates a magnetic field. The magnetic lines of flux cut through the air around the coil. If a ferrous material, such a solid bar of iron is inserted into this coil, certain effects known as eddy currents are induced to flow in the metal bar. This causes localised heating, and ultimately heats up the metal bar.
A hexagonal screw in the red hot zone. Estimated at ~700 degrees C, from the colour of the steel.
Input frequency is ~300kHz for the coil. This seems to deliver maximum heating power.”