Materials Transactions Online

Materials Transactions, Vol.54 No.03 (2013) pp.314-318
© 2013 The Japan Institute of Metals

Fracture Toughness for Brittle Fracture of Elastic and Plastic Materials

Yoshikazu Tanabe

National Museum of Nature and Science, Tsukuba 305-0005, Japan

The crack energy density causes a new expression of fracture toughness for brittle fracture, together with the concept of Barenblatt’s characteristic distance dc of cohesive zone at the edge of the crack. The Griffith’s formula for fracture toughness is modified by the ratio of σTT, which σT is the true fracture stress and ΣT the maximum strength of the material obtainable by ordinary processing. The fracture toughness of elastic-plastic material, K*Ic for brittle fracture is described by the product of σT and the root of the observed absorption energy by Charpy impact test corrected for instrumental effect, . The characteristic distance dc depends linearly on the released elastic energy, which is the physical basis of above-mentioned estimation formula.

(Received 2012/10/18; Accepted 2012/12/10; Published 2013/02/25)

Keywords: fracture toughness, crack energy density, true fracture stress, corrected Charpy impact value, Barenblatt’s characteristic distance

PDF(Free)PDF (Free) Table of ContentsTable of Contents


  1. T. Oda, M. Nakamura and H. Kawakami: J. Jpn. Inst. Met. 39 (1975) 725-735 (in Japanese).
  2. T. Oda, M. Nakamura and H. Kawakami: Mitsubishi Heavy Industries Technical Rev. 12 (1975) 100-107 (in Japanese).
  3. M. Nakamura and Y. Tanabe: Bull. Natl. Mus. Nat. Sci., E 31 (2008) 15-24 (in Japanese).
  4. K. Watanabe: Trans. Jpn. Soc. Mech. Eng. 51 (1985) 873-882 (in Japanese).
  5. K. Watanabe: Trans. Jpn. Soc. Mech. Eng. 47 (1981) 406-415 (in Japanese).
  6. K. Watanabe: Trans. Jpn. Soc. Mech. Eng. 48 (1982) 1226-1236 (in Japanese).
  7. K. Watanabe: Prep. Jpn. Soc. Mech. Eng. No. 804-1 (1980) 91-94 (in Japanese).
  8. G. I. Barenblatt: Adv. Appl. Mech. 7 (1962) 55-129.
  9. J. N. Goodier: Fracture, An Advance Treatise, (ed. H. Liebowitz, Academic Press, 1968), vol. II (Mathematical Fundamentals), Chap. 1.
  10. A. A. Griffith: Proc. 1st Intern. Congr. Appl. Mech., Delft (1924) pp. 55-63.
  11. H. Okamura: Introduction to Linear Fracture Mechanics, (Baifukan Co., Ltd., 2006) (in Japanese).
  12. M. Shiratori, T. Miyoshi and H. Matsushita: Computational Fracture Mechanics, (Jikkyo Shuppan Co., Ltd., 1999) (in Japanese).
  13. T. L. Anderson: Fracture Mechanics —Fundamental and Applications—, (CRC Press, Taylor & Francis, 2005).
  14. G. Irwin: Fracturing of Metals, (American Society for Metals, 1948) pp. 147-166.
  15. E. Orowan: Fatigue and Fracture of Metals, (ed. W. M. Murray, Wiley, 1950) pp. 139-167.
  16. T. Kobayashi and I. Yamamoto: Bull. Jpn. Inst. Met. 32 (1993) 151-159 (in Japanese).
  17. T. Kobayashi, M. Niinomi, Y. Koide and K. Matsunuma: Trans. JIM 27 (1986) 775-783.
  18. M. Asano, T. Kobayashi, M. Nawa and K. Niihara: J. Jpn. Inst. Met. 60 (1996) 1222-1228 (in Japanese).
  19. N. Tsuji: Tetsu-to-Hagane 88 (2002) 359-369 (in Japanese).


© 2013 The Japan Institute of Metals
Comments to us :