High temperature oxidation and ignition of some metallic materials in fluorine

When 3-mm-diameter cylindrical samples are heated by direct passage of an electric current through them, it is observed that titanium, molybdenum, tungsten-niobium alloy, nickel, iron, carbon steel, and stainless steel in gaseous fluorine (p=0.2 MPa) ignite through a thermal explosion mechanism, while copper, its alloys, and aluminum ignite when the melting point of the fluoride film is reached. The critical ignition temperatures of these materials are established. Experimental data on the high temperature oxidation kinetics are used to calculate the pertinent parameters of the Arrhenius for the preignition interaction of the steels and nickel with fluorine. Translated fromFizika Goreniya i Vzryva, Vol. 34, No. 4, pp. 34–42, July–August 1998.