what are some of the applications of this process?
Its used in welding thin workpieces, manufacture of space vehicles, bicycle industry, etc.
Gas tungsten arc welding
While the aerospace industry is one of the primary users of gas tungsten arc welding, the process is used in a number of other areas. Many industries use GTAW for welding thin workpieces, especially nonferrous metals. It is used extensively in the manufacture of space vehicles, and is also frequently employed to weld small-diameter, thin-wall tubing such as that used in the bicycle industry. In addition, GTAW is often used to make root or first-pass welds for piping of various sizes. 
what is gas tungsten arc welding? It is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. is there a gas used in this welding process? Yes, shielding gas what specific gas is used? Helium why are such gases used in this process? To protect the welding area from atmospheric gases.
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Gas tungsten arc welding [SEP] Applications
While the aerospace industry is one of the primary users of gas tungsten arc welding, the process is used in a number of other areas. Many industries use GTAW for welding thin workpieces, especially nonferrous metals. It is used extensively in the manufacture of space vehicles, and is also frequently employed to weld small-diameter, thin-wall tubing such as that used in the bicycle industry. In addition, GTAW is often used to make root or first-pass welds for piping of various sizes. In maintenance and repair work, the process is commonly used to repair tools and dies, especially components made of aluminum and magnesium.