1. 1) G.Krauss: Steels, Heat Treatment and Processing Principles, ASM International, Materials Park, OH, (1989), 214.
2. 2) M. Sakamoto, T. Teshima and K. Nakamura: Nippon Steel Tech. Rep., 412(2019), 135 (in Japanese).
3. 3) A.H. Cottrell and B.A. Bilby: Proc. Phys. Soc. A, 62(1949), 49.
4. 4) H.Suzuki: Dislocations and Mechanical Properties of Crystals, John Wiley and Sons, New York, (1957), 361.
5. 5) R.L. Fleischer: Acta Metall., 10(1962), 835.