Uses: A rare gas. Used as a shield gas for arc welding (cutting) stainless steel, magnesium, aluminum, and other alloys. Also used in smelting of steel, aluminum, titanium and zirconium. Argon discharge purple glow, but also for lighting technology and filling fluorescent lamps, photocell, lighting tubes. 
During the brewing process, the fillings in the beer barrel displace oxygen to prevent the raw material in the beer barrel from being oxidized to acetic acid.
Heat treatment process is also used to replace nitrogen and ammonia, the effect is more than nitrogen and ammonia, stainless steel heat treatment using argon to protect the bending effect is better not easy to break.