1. 1) K. Hashimoto, H. Doi, K. Kasahara, T. Tsujimoto, and T. Suzuki: J. Japan Inst. Metals, 54 (1990), 539.
2. 2) K. Hashimoto, H. Doi, and T. Tsujimoto: Collected Abstracts of the 1984 Autumn Meeting of Japan Inst. Metals, (1984), 464.
3. 3) M. J. Blackburn and M. P. Smith: U. S. Patent, No. 4292077 (1981).
4. 4) T. Tamura, T. Kawabata, and O. Izumi: Collected Abstracts of the 1987 Autumn Meeting of Japan Inst. Metals, (1987), 313.
5. 5) E. Kobayashi, M. Yoshihara and R. Tanaka: J. Japan Inst. Metals, 53 (1989), 251.