Resistance heating is the electric heating of an object using the heat generated by the Joule effect of current flowing through a conductor. Resistance heating can be divided into two categories: indirect resistance heating and direct resistance heating.
Indirect resistance heating is to let current pass through electric heating elements or conductive media, such as resistance wire, thermistor (PTC), electric heating film, etc., to make the electric heating element heat first, and then use the heat generated by the electric heating element to conduct heat, heat convection or heat radiation, etc. The method indirectly heats the target object. The traditional methods of using electric heating elements embedded in the mold to heat the mold all belong to indirect resistance heating.