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Official Journal of the Japan Wood Research Society

Examination of the onset of stable crack growth under fracture toughness testing of paper


Successive temperature distribution images around the notch tips during fracture toughness testing of paper were obtained by means of an infrared thermography system. Analysis of the images gave the critical times when the temperature significantly rose at the notch tip and when the distance between two maximum temperature spots started to decrease during the testing. Other successive microscopic images around the notch tips showed the relation between crack opening and displacement and the transitional point of the relation. The onset of stable or unstable crack growth as indicated in these critical times and the point agree with each other. For the specimen with a small width, an unstable crack starts to grow at the maximum load point without the stable crack growth period. On the other hand, a stable crack grows before the maximum load point unless the specimen width is small.The period of the stable crack growth increases with an increase in width. Differing from the methods based on thermal images to determine the onset of crack growth, the microscopic method is applicable at a wide range of strain rates and is thus suitable for quasistatic fracture toughness testing.


  1. 1.

    Seth RS, Robertson AG, Mai YW, Hoffman JD (1993) Plane stress fracture toughness of paper. TAPPI J 76(2):109–116

    CAS  Google Scholar 

  2. 2.

    Seth RS, Page DH (1975) Fracture resistance: a failure criterion for paper. TAPPI J 58(9):112–117

    Google Scholar 

  3. 3.

    Uesaka T, Okaniwa H, Murakami K, Imamura R (1979) Tearing resistance of paper and its characterization (in Japanese). Jpn TAPPI J 33:403–409

    Article  Google Scholar 

  4. 4.

    Steadman R, Sloane M (1990) Fracture toughness — a paper test for the 1990's. In: Proceedings of the 44th Appita Conference, C3, pp 1–16

  5. 5.

    Yuhara T, Kortschot MT (1993) The J-integral as a parameter for characterising the fracture toughness of paper. In; Baker CF (ed) Transactions of the 10th Fundamental Research Symposiun held at Oxford, vol 2. PIRA International, Leatherhead, Surry, UK. pp 783/806

    Google Scholar 

  6. 6.

    Wellmar P, Fellers C, Delhage L (1997) Fracture toughness of paper-development of a test method. Nordic Pulp Paper Res J 12(3):189–195

    CAS  Article  Google Scholar 

  7. 7.

    JSME Standard S-001 (1981) Standard method of test for elasticplastic fracture toughness JIc (in Japanese). Japan Society of Mechanical Engineers

  8. 8.

    Yuhara T, Kortshot MT (1993) A simplified determination of the J integral for paper. J Mater Sci 28:3571–3580

    CAS  Article  Google Scholar 

  9. 9.

    Choi D, Thorpe JL (1992) Progressive deformation at the crack tip in paper during mode I fracture, part 1-bond paper. TAPPI J 75(10):127–134

    CAS  Google Scholar 

  10. 10.

    Tanaka A, Otsuka Y, Yamauchi T (1997) In-plane fracture toughness testing of paper using thermography. TAPPI J 80(5):222–226

    CAS  Google Scholar 

  11. 11.

    Tanaka A, Yamauchi T (1997) Crack propagation of paper under fracture toughness testing. J Pack Sci Technol Jpn 6:324–332

    CAS  Google Scholar 

  12. 12.

    Uesaka T (1983) Design for testing paper and paperboard. In: Mark RE (ed) Handbook of physical and mechanical testing of paper and paperboard, vol 1. Marcel Dekker, New York, pp 77–113

    Google Scholar 

  13. 13.

    Yamauchi T, Okumura S, Noguchi M (1990) Acoustic emission as an aid for investigating the deformation and fracture of paper. J Pulp Paper Sci 16(2):J44-J47

    Google Scholar 

  14. 14.

    Yamauchi T, Okumura S, Noguchi M (1993) Application of thermography to the deforming process of paper materials. J Mater Sci 28:4549–4552

    CAS  Article  Google Scholar 

  15. 15.

    Shiratori M, Miyoshi T, Matsushita H (1980) Computational fracture mechanics. Jitsukyo Publishing, Tokyo, p 45

    Google Scholar 

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Correspondence to Tatsuo Yamauchi.

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Yamauchi, T., Hirano, H. Examination of the onset of stable crack growth under fracture toughness testing of paper. J Wood Sci 46, 79–84 (2000).

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Key words

  • Fracture toughness
  • Crack opening displacement
  • J integral
  • Crack growth
  • Infrared thermography