Application of low inert infrared heaters for soldering processes

Low inert infrared (IR) heaters are made from thin metal sheets. A special coating on the surface of the heaters ensures emissivity about 0.9. The heaters are warmed up directly by electric current. The surface temperature and spectral distribution of this type of heater may be varied by electronic control, making them very suitable for soldering of electronic components, especially for SMDs on PCBs. The construction allows flowing air (or inert gas) through them. Experimental equipment for soldering of electronic components on PCBs was designed and produced in our laboratory. The following experiments were carried out: the temperature distribution on the PCB and electronic components, with and without convection heating, were measured. The possibility for realization of different time/temperature profiles was investigated. Opportunities of utilization of this technology for different kinds of solder pastes and for different kinds of electronic components were evaluated.