The third-most abundant gas in the Earth’s atmosphere, Argon is mostly used as an inert shielding gas in welding and other high-temperature industrial processes where ordinarily nonreactive substances become reactive. It has low thermal conductivity and is the cheapest alternative, since it occurs naturally in the air, when Nitrogen is not sufficiently inert.
Argon is used in some high-temperature industrial processes where ordinarily non-reactive substances become reactive. For example, an argon atmosphere is used in graphite electric furnaces to prevent the graphite from burning. It is also used to replace gases like Nitrogen and Oxygen when their presence might cause defects in the material. Furthermore, it is also used as a shielding gas in some types of arc welding such as gas metal arc welding and gas tungsten arc welding, as well as in the processing of titanium and other reactive elements. An argon atmosphere is also used for growing crystals of silicon and germanium. Argon can also be used as a fire extinguisher when water or foam may damage valuable equipment.
Argon displaces oxygen and moisture and helps extend the shelf-lives of the packaged contents. Aerial oxidation, hydrolysis, and other chemical reactions that degrade the products are retarded or prevented entirely. Moreover, in wine-making, the gas is used in a variety of activities to provide a barrier against oxygen at the liquid surface, which can spoil wine by fuelling both microbial metabolism and standard redox reactions.
Argon helps in preserving the filaments of incandescent lights from oxidation at high temperatures. It can also produce beautiful lilac or blue light when used in gas-discharge lamps.