n (1944) (electronic heating, RF heating, radio-frequency heating, high-frequency heating, microwave heating) The process of heating poor (but polar) conductors of electricity (dielectrics) by means of high-frequency fields. At frequencies above 10 MHz sufficient heat for rapid sealing and welding of many plastics can be generated by low, safe voltages. The process of dielectric heating consists of placing the material to be heated between two shaped electrodes that are connected to a high-frequency current supply. These electrodes act as the plates of a capacitor and the material serves as the dielectric separating them. As the field changes polarity, charge-bearing atoms or groups of the dielectric undergo reorientation in an effort to keep their positive poles toward the electrode that is momentarily negative, thus generating molecular friction that is dissipated as heat. The theoretical rate of heating is given by the equation
$$\pi \, \cdot f \cdot \cdot
