Why is an argon atmosphere used during titanium sponge production?

An argon atmosphere is used during the production of titanium sponge to prevent the metal from becoming contaminated by air or moisture.1

Titanium is highly reactive at the elevated temperatures required for its extraction—typically between 800 °C and 1,000 °C—and it readily reacts with elements such as oxygen and nitrogen. By conducting the reduction process within an inert argon environment, manufacturers ensure the purity and integrity of the resulting titanium sponge, as exposure to atmospheric gases would otherwise compromise the material's properties.21