Helium

Helium is second lightest element, which is one of the most precious natural resources. It wouldn’t chemically combine with any element at any temperature. It’s a non-toxic, non-flammable, and non-explosive element, and its chemical insensitivity makes it apt for a wide range of applications. Being an inert element, Helium finds application for arc welding in the form of a shielding gas. Its voltage gradient is high, due to which it transfers higher heat to weld than argon does at same arc lengths. This additional heat is necessary for high-speed welding. Itself an output of radioactive decay process of billions of years, beneath earth's surface, the element, helium, is not impacted by radiation. Radioactive immunity, in addition to the exceptional heat transfer makes Helium a perfect heat transfer agent for the gas-cooled nuclear reactor.