When stainless steel is welded, the intense heat generated causes chromium depletion, so an iron rich zone is left around the weld. The high concentration of surface iron, together with the high welding temperatures, causes the iron to immediately oxidize. This results in the characteristic blue and a brown discolouration around the weld.
The discoloured area corrodes easily, as chromium isn’t present in high enough concentrations to protect the metal.
The TIG Brush® has been designed to rapidly remove the discoloured oxides and passivate the underlying surface, without altering the look and finish of the metal. The features which enable the TIG Brush® to do this quickly and in a safe manner are explained below.