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Reduction of titanium oxide in the presence of nickel by nonequilibrium hydrogen gas

Published online by Cambridge University Press:  31 January 2011

Hidehiro Sekimoto ,
Tetsuya Uda ,
Yoshitaro Nose ,
Shigeo Sato ,
Hiroaki Kakiuchi  and
Yasuhiro Awakura
Hidehiro Sekimoto*
Affiliation:
Department of Materials Science and Engineering, Graduate School of Engineering, Kyoto University, Kyoto 606-8501, Japan
Yoshitaro Nose
Affiliation:
Department of Materials Science and Engineering, Graduate School of Engineering, Kyoto University, Kyoto 606-8501, Japan
Shigeo Sato
Affiliation:
Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
Hiroaki Kakiuchi
Affiliation:
Department of Precision Science and Technology, Division of Precision Science &Technology and Applied Physics, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan
Yasuhiro Awakura
Affiliation:
Department of Materials Science and Engineering, Graduate School of Engineering, Kyoto University, Kyoto 606-8501, Japan
*
a) Address all correspondence to this author. e-mail: hidehiro.sekimoto@t14.mbox.media.kyoto-u.ac.jp
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Abstract

We investigated the reduction of TiO2 in the presence of Ni by nonequilibrium hydrogen gas, including low-temperature hydrogen plasma at 800 °C and supercooled monatomic hydrogen at 1000 °C. TiO2 was reduced to Ti2O3, which is not in equilibrium phase, by low-temperature hydrogen plasma. The results of x-ray diffraction and energy dispersive x-ray analysis in experiments at 1000 °C indicate that the thermodynamical reduction potential of supercooled monatomic hydrogen is almost the same as atmospheric hydrogen gas. However, the wide Ti3O5 layer formed only in the case of the reduction at 1000 °C by supercooled monatomic hydrogen. With these experimental facts, we speculate that the reduction mechanism by nonequilibrium hydrogen consists of two steps; the releasing energy process and the relaxation process. We can explain the difference of reduction products by nonequilibrium hydrogen gas on the assumption of the rate of the relaxation process between 800 and 1000 °C.

Keywords

Phase equilibriaSurface reactionTi
Type
Articles
Information
Journal of Materials Research , Volume 24 , Issue 7 , July 2009 , pp. 2391 - 2399
Copyright
Copyright © Materials Research Society 2009

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References

1Hagiwara, M.: New evolution in titanium research and development in Japan. J. Jpn. Inst. Light Metals 55, 532 (2005).CrossRefGoogle Scholar
2Scanlan, R.M., Malozemoff, A.P., and Larbalestier, D.C.: Superconducting materials for large scale applications. Proc. IEEE 92, 1939 (2004).CrossRefGoogle Scholar
3Chen, G-Z., Fray, D.J., and Farthing, T.W.: Direct electrochemical reduction of titanium dioxide to titanium in molten calcium chloride. Nature 401, 361 (2000).CrossRefGoogle Scholar
4Uda, T. and Okabe, T.H.: Reduction process of titanium oxide using molten salt. Titanium Jpn. 50, 325 (2002).Google Scholar
5Okabe, T.H., Suzuki, R.O., Oishi, T., and Ono, K.: Thermodynamic properties of dilute titanium-oxygen solid solution in beta phase. Mater. Trans., JIM 32, 485 (1991).CrossRefGoogle Scholar
6Meschter, P.J. and Worrel, W.L.: An investigation of high-temperature thermodynamic properties in the Pt–Ti system. Metall. Trans. A 7, 299 (1976).CrossRefGoogle Scholar
7Shioi, R., Imashuku, S., Uda, T., and Awakura, Y.: Reduction of titanium oxide in the presence of platinum and consideration of a new smelting method for titanium, in Abstracts of the Spring Meeting for the Mining and Material Processing Institute of Japan, Vol. 89 (2006).Google Scholar
8Bullard, D.E. and Lynch, D.C.: Reduction of titanium dioxide in a nonequilibrium hydrogen plasma. Metall. Mater. Trans. B 28, 1069 (1997).CrossRefGoogle Scholar
9Zhang, Y-W., Ding, W-Z., Lu, X-G., Guo, S-Q., and Xu, K-D.: Reduction of TiO2 with hydrogen cold plasma in DC pulsed glow discharge. Trans. Nonferrous Met. Soc. China 15, 594 (2005).Google Scholar
10Huet, S., Belmonte, T., Thiébaut, J.M., Bockel, S., and Michel, H.: Reduction of TiO2 assisted by a microwave plasma at atmospheric pressure. Thin Solid Films 475, 63 (2005).CrossRefGoogle Scholar
11Chattopadhyay, G. and Kleykamp, H.: Phase equilibria and thermodynamic studies in the titanium-nickel and titanium-nickeloxygen systems. Z. Metallkd. 74, 182 (1983).Google Scholar
12Barin, I.: Thermodynamic Data of Pure Substances, 3rd ed. (Wiley-VCH, Weinheim, Germany, 1995).CrossRefGoogle Scholar
13Liang, H-Y. and Jin, Z-P.: A reassessment of the Ti–Ni system. Calphad 17, 415 (1993).Google Scholar
14Kaneya, K. and Okayama, S.: Penetration and energy-loss theory of electrons in solid targets. J. Phys. D: Appl. Phys. 5, 43 (1982).CrossRefGoogle Scholar
15Cullity, B.D.: Elements of X-ray Diffraction, 2nd ed. (Addison-Wesley Publishing Co., Reading, MA, 1978).Google Scholar
16Jacob, K.T., Chandra, A., and Mallya, R.M.: An assessment of the reduction potential of hydrogen plasma. Z. Metallkd. 91, 401 (2005).Google Scholar
17Ichii, K., Nishimoto, A., Nakao, K., and Akamatsu, K.: Low temperature nitriding of austenitic stainless steel. J. Surf. Fin. Soc. Japan 54, 200 (2003).Google Scholar
18Straboni, A., Pichon, L., and Girardeau, T.: Production of stable and metastable phases of zirconium nitrides by NH3 plasma nitridation and by double ion beam sputtering of zirconium films. Surf. Coat. Technol. 125, 100 (2005).CrossRefGoogle Scholar
19Kondoh, E., Fukasawa, M., and Ojimi, T.: Reduction of thin oxidized copper films using a hot-filament hydrogen radical source. J. Vac. Sci. Technol., A 25, 415 (2007).CrossRefGoogle Scholar