Research into GTA automatic soft soldering technology for solar energy collector components

This article presented research into procedures for the development of gas tungsten arc (GTA) automatic soft soldering of solar absorber components, i.e. joining of tubes to copper foil by means of brazing with Solar Cast 5 soft self-fluxing solder paste. The brazing process was carried out in two ways: joining of a flat copper foil to the tube, and joining with formation of a semi-circular channel with a diameter equal to that of the tube, inside the copper foil. The properties of the finished joints were determined by means of metallographic examination, hardness measurements, static tensile tests as well as thermal conduction tests. The results of these tests proved the occurrence of an area of GTA brazing parameters which would ensure high-quality absorber joints between the tube and the copper foil.