OXIDATION OF Fe-Nb ALLOYS UNDER 0.1 Mpa PURE OXYGEN AT 600─800℃
NIU Yan; WU Weitao; FGESMUNDO; FC.RIZZO;(State Key Laboratory for Corrosion and Protection; Institute of Corrosion and Protection of Metals; Chinese Academy of Sciences; Shenyang 1 100015 )(Istituto di Chimica; Facolta di Ingegneria; Universita' di Genova; Fiera del Mare;Pad. D; 16129 Genova; Italy )(Departamento de Ciencia dos Materiais e Metalurgia; Pontificia Universidade Catolica do Rio de Janeiro; Caixa Postal 38008; 22453-900; RJ; Brazil )(Manuscript received 1995-05- 19; in revised form 1 995-09-08)
Cite this article:
NIU Yan; WU Weitao; FGESMUNDO; FC.RIZZO;(State Key Laboratory for Corrosion and Protection; Institute of Corrosion and Protection of Metals; Chinese Academy of Sciences; Shenyang 1 100015 )(Istituto di Chimica; Facolta di Ingegneria; Universita' di Genova; Fiera del Mare;Pad. D; 16129 Genova; Italy )(Departamento de Ciencia dos Materiais e Metalurgia; Pontificia Universidade Catolica do Rio de Janeiro; Caixa Postal 38008; 22453-900; RJ; Brazil )(Manuscript received 1995-05- 19; in revised form 1 995-09-08). OXIDATION OF Fe-Nb ALLOYS UNDER 0.1 Mpa PURE OXYGEN AT 600─800℃. Acta Metall Sin, 1996, 32(3): 294-302.
Abstract The oxidation of two Fe-Nb alloys containing 15 and 30% Nb(mass fraction) has been studied at 600─800℃ under 0.1 MPa pure oxygen.The reaction followed the parabolic rate law to a reasonable approximation with rate constants much lower than that for the oxidation of pure iron under the same condition. Internal oxidation and depletion of niobium in the alloy have not been observed. The external scales were composed of Fe2O3 and a dispersion of double Fe-Nb oxide, while FeO and Fe2O3 were not observed.The oxidation behavior of these alloys is interpreted with reference to an approximate phase diagram of the ternary system Fe-Nb-O, taking into account the effects of the low solubility of niobium in the base metal and of the presence of two metallic phases in the alloy. Correspondent: NIU Yan, State Key Laboratory for Corrosion and Protection, ICPM Shenyang 110015