1. 1) M. Kawakami, M. Ooishi, T. Takenaka, and T. Suzuki, Proc. 5th Intnl. Conf. Molten Slags, Fluxes and Salts ’97, 477 (1997).
2. 2) M. Kawakami and T. Kusamichi, Japanese Patent, H06-146094, (1994) (in Japanese).
3. 3) M. Hansen, ed., Constitution of Binary Alloys, 2nd. Ed., McGraw-Hill, N.Y., p. 725 (1958).
4. 4) T. Tomonari, A. Kirihara, O. Watanabe, T. Noda, and S. Ogi, Titanium and Zirconium, 15, 5 (1967) (in Japanese).
5. 5) I. Barin and O. Knacke, Themochemical properties of Inorganic Substances, Springer Verlag, Berlin (1973).