Elektrisktermisk

Elektrisktermisk (electrothermal) refers to the interplay between electrical energy and thermal energy in systems where electricity is converted into heat or where temperature differences influence electrical properties. The term covers resistive heating, thermoelectric phenomena, and electrothermal actuation.

Resistive heating (Joule heating) occurs when an electric current passes through a conductor, raising its temperature proportional to I^2R. This mechanism underpins electric heaters, soldering irons, and microheaters in sensors and laboratory devices. Thermoelectric effects arise when a temperature gradient within a material or at a junction generates voltage (Seebeck effect) or when current causes heating or cooling at junctions (Peltier effect). These effects enable solid-state cooling or heating modules and temperature sensing, but also require thermal management considerations in electronics.

Electrothermal actuation uses localized heating to induce thermal expansion or bending in materials, commonly in microelectromechanical systems (MEMS) and microfluidic components. Materials such as polysilicon, metal traces, and composite films serve as heaters to drive actuators, valves, or switches. In analytical instrumentation, electrothermal furnaces are used to atomize samples for spectroscopy (electrothermal atomic absorption spectroscopy).

Modeling electrothermal systems involves coupled electrical and thermal transport, incorporating electrical resistance, heat generation, and heat diffusion. Design considerations include thermal resistance, heat transfer coefficients, material properties, and safety. The field intersects with thermoelectrics, microfabrication, materials science, and energy engineering.