Assertion: argon | /r/HasProperty | nitrogen
Facets:
value: sometimes
type: TEMPORAL
Source sentences:
text: The second type, tungsten inert gas shielded welding (GTAW),inert gas uses argon (or helium, sometimes nitrogen) as shielding gas, and is mainly used for in-situ welding (welding, where the edges of the material melt to form welding), thus the process is expensive because of the use of argon.
text: This argon is the third most common component of air, the nitrogen and oxygen.