Novel Estimation of Critical Frontal Process Zone of Ceramics by a Single-Edge V-Notched-Beam Technique


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A novel estimation for the critical size of the frontal process zone of ceramics is proposed using a single-edge V-notched beam (SEVNB) technique. A three-point flexure test is carried out on aluminum titanate ceramics containing a sharp V-shaped notch with different depth. An exact solution of the critical local stress is analyzed at a critical distance from the notch tip. The critical frontal process zone size is determined as the distance between the notch tip and the point where the critical local stress equals the flexural strength of specimens without notches, based on the local fracture criterion and the Griffith-Irwin criterion. The critical size of the frontal process zone, the fracture toughness and the flexural strength were also estimated for several materials, such as, alumina, porous alumina, and alumina-based nanocomposites. The relationship between these mechanical properties indicated that there was an almost linear relationship between the fracture toughness and the resultant of strength and square root of the critical frontal process zone size, and that both of them must be increased to improve the fracture toughness of ceramics.



Key Engineering Materials (Volumes 280-283)

Edited by:

Wei Pan, Jianghong Gong, Chang-Chun Ge and Jing-Feng Li






C. H. Chen and H. Awaji, "Novel Estimation of Critical Frontal Process Zone of Ceramics by a Single-Edge V-Notched-Beam Technique", Key Engineering Materials, Vols. 280-283, pp. 1745-1750, 2005

Online since:

February 2007




[1] R.F. Pabst, J. Steeb and N. Claussen: in Fracture Mechanics of Ceramics, Vol. 4. Edited by R.C. Bradt, D.P.H. Hasselman and F.F. Lange (Plenum Press, New York, 1978), p.821.

[2] H. Awaji and Y. Sakaida: J. Am. Ceram. Soc. Vol. 73 (1990), p.3522.

[3] H. Awaji, T. Watanabe, T. Yamada, Y. Sakaida, H. Tamiya and H. Nakagawa: Trans. Japan Soc. Mech. Eng. Vol. 56 (1990), p.1148.

[4] A.A. Griffith: Trans. Roy. Soc. London Vol. A221 (1920), p.163.

[5] M. Strandberg: Engng. Fract. Mech. Vol. 69 (2002), p.403.

[6] D. Broek: Elementary Engineering Fracture Mechanics, 4th ed. (Kluwer, 1986).

[7] B.R. Lawn: Fracture of Brittle Solids, 2nd ed. (Cambridge Univ. Press, 1993).

[8] H. Awaji, T. Watanabe and Y. Sakaida: Ceram. Int. Vol. 18 (1992), p.11.

[9] S.M. Choi, S. Honda, T. Nishikawa, H. Awaji, T. Sekino and K. Niihara: J. Soc. Mater. Sci. Japan Vol. 52 (2003), p.1374.

[10] S.M. Choi: Structural Integrity and Fracture, Eds. A.V. Dyskin, X. Hu and E. Sahouryeh (Swets & Zeitlinger, Lisse, 2002).

[11] N. Kishi: Master-degree thesis, 2003, Nagoya Institute of Technology (in Japanese).

[12] S. Usami, H. Kimoto, I. Takahashi and S. Sida: Eng. Fract. Mech. Vol. 23 (1986), p.745.

[13] H. Kimoto, S. Usami and H. Miyata: Trans. Jpn. Soc. Mech. Eng. Vol. 51 (1985), p.2482.

[14] I.D. Alecu, R.J.T. Stead: Korean Journal of Ceramics Vol. 5 (1999), p.78.

[15] H. Awaji: Strength of Ceramic Materials. (Corona Pub., Tokyo, 2001).

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