Arc welding in an inert gas shield with a non-consumable tungsten electrode (T.I.G. - Tungsten Inert Gas or G.T.A.W. - Gas Tungsten Arc Welding) is a procedure in which the heat necessary to make the welding is supplied by an electric arc which is maintained between a non-consumable electrode and the workpiece. The electrode used to conduct the current is in tungsten or tungsten alloy. The welding zone, the melted metal and the non-consumable electrode are weatherproof thanks to the inert gas which is supplied by the electrode holder torch. The TIG welding procedure can be used with the addition of external weld material (welding rod) or by melting the base material by means of the heat effect produced by the electric arc.
