A nonstandard term for GAS TUNGSTEN ARC WELDING. See GAS TUNGSTEN ARC WELDING.
TIG as a Nonstandard Term. Although the terms TZG and MZG are popularly used, they do not accurately reflect the technology of the processes. In the document ANSIIAWS A3.0, Standard Welding Terms and Definitions, the American Welding Society (AWS)
Definitions and Symbols Committee has stated a preference for GTAW (gas tungsten arc welding) because it is a more definitive term than TZG.
The gas tungsten arc process was originally used with an inert gas as the arc- shielding atmosphere. The term tungsten inert gas (TZG) became popular. The later application of non-inert, i.e., active, gases for arc shielding rendered the term TIG inaccurate. To remove that discrepancy, the term tungsten active gas (TAG) was proposed by some. With that terminology, the welding of stainless steel with argon is referred to as a TZG welding process, and if hydrogen is added to the argon shielding gas, the welding process becomes TAG. If the latter gas mixture is used for welding a noble metal, the welding process would then revert to TIG. Thus the name of the welding process depends not only on the composition of the shielding gas but also on the base metal composition. Logically, such terminology would be comparable to making the name of the shielded metal arc welding process dependent on the type of electrode covering and the composition of the base metal.
The proponents of TZG correctly cite its simplicity, brevity, and ease of pronunciation. However, “tungsten inert gas,” by itself is incomplete. Only when the word welding is added is the term complete and may be logically compared with gas tungsten arc welding. The term would be TZGW, and it would lose some of the cited advantages.
Arguments similar to those made in support of GTAW also apply to gas metal arc welding (GMAW) versus metal inert gas (MIG) welding. Both GTAW and GMAW are part of a coherent letter designation system that has been developed by the Definitions
Subcommittee of AWS for all of the welding and allied processes. Haphazard changes cannot be made without damage to the letter system as a whole. The Definitions Subcommittee prefers the terms gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW), with modifiers to denote the variations of the processes. The terminology in the document, ANSIIAWS A3.0, Standard Welding Terms and Def- nitions, has been widely accepted by such organizations as the American Society for Metals, the American Society of Mechanical Engineers, and the Department of Defense, as well as the American Welding Society. .