1. 1) S.Fuchizawa : Tetsu-to-Hagané, 90 (2004), 451.
2. 2) H.Abe : J. Jpn. Soc. Technol. Plast., 45 (2004), 92.
3. 3) Y.Kuriyama : J. Jpn. Soc. Technol. Plast., 45 (2004), 715.
4. 4) JIS Z2241 Method of tensile test for metallic materials, JIS Z2201 Test pieces for tensile test for metallic materials.
5. 5) JIS G3445 Carbon steel tubes for machine structural purposes, 8.