Determination of GTA and GMA welding arc temperatures

The welding arc has been successfully used in the welding industry for many years. However, not all physical phenomena assciated with it have, as yet, been fully understood and explained. Consequently, there arises a need to investigate the work of the arc during GTA and GMA processing. Models of the welding arc are being constructed with a view to gaining a better insight into the occurring phenomena1–5 including arc temperature since this is the parameter which influences all of the changes taking place.6 Investigations into the welding arc temperature lead to a better understanding of its working, The temperature of the welding arc varies from 5 000 to 30 000 K depending on the welding parameters and the type of shielding gas. After the introduction into the arc's plasma of easily ionized atoms of sodium or potassium, a maximum temperature of the order of 6 000 K can be reached.7