Experimental results-based estimation of cooling time during the TIG surfacing of steels performer with and without preheating

The paper shortly characterises the structure of the separate areas of the heat affected zone which occurs in the structural steels during welding and surfacing. It presents the methodology of thermal cycles measuring while argon shielded TIG surfacing of steel plates SM400A. Surfacing was conducted in two variants, i.e. without preheating and with preheating before surfacing. Research resulted in the developing of diagrams determining the value of the maximum temperature of the thermal cycle in the specific place of the element being surfaced for the given heat input Q as well as diagrams enabling the determination of cooling time of a padding weld, assuming that maximum temperature of the thermal cycle in the selected point of the component being surfaced is known for the determined heat input Q during TIG surfacing with and without preheating. Keywords: welding thermal cycle, TIG process, heat input q, preheating, cooling time