Home/Technical Glossary/Thermode Thermode Pulsed-Heated Hot-Bar Reflow Soldering is a selective soldering process where two pre-fluxed, solder coated parts are heated to a temperature sufficient to cause the solder to melt, flow, and solidify, forming a permanent electro-mechanical bond between the parts and solder. Pulse heated soldering differs from the traditional soldering process in that the reflow of solder is accomplished using a heating element called a “thermode“ or “hot bar” which is heated and cooled down for each connection. Read the Reflow Soldering Process Overview or Part Design Guidelines for Reflow Soldering Flex to PCB’s for more information.