Infrared Radiation Spectrum Control During Soldering Processes Applying Low Inert Heaters

The article deals with investigation of IR radiation spectrum control during soldering of surface mounted devices (SMD) to printed circuit boards (PCB) by application of new kind of radiation heating equipment. It is suitable for electronic components soldering to PCB using conventional and lead free solder pastes, different kinds of annealing and others. By application of low inert radiation heaters for the middle IR region and microprocessor control of their operation versatile energy saving installation proper for all kinds of solder pastes is made. This equipment allows realizing precise control (in situ) of the temperature on the PCB during the soldering processes, possibility of individual temperature profile for every printed board during the soldering process in dependence of its size, electronic components density and others. By electronic control of heating regimes the heaters´ surface temperature may vary in a wide range from 430 K to 1300 K. Due to low inertia of the heaters temperature changes may be realized very quickly, in practice for a few seconds. This allows controlling radiation spectra of energy emitted to PCB and electronic components according to their spectral characteristics and achievement of optimal heating regime for every PCB.