Skip to main content
Log in

On the estimation of the toughness of surface microcracks

  • Published:
International Journal of Fracture Aims and scope Submit manuscript

Abstract

Hardness testing is a method frequently used for evaluating the resistance of body surfaces to the influence of contact loading. The Vickers hardness test is applied for this purpose in a case when the material is sufficiently ductile and no cracks occur in the corners of the indents. Testing of the surface hardness of such materials as glass and ceramics on the basis of the Vickers testing method must take into account the energy that is spent on crack spreading. This paper describes a more exact and accurate method for evaluating resistance to microcrack formation on the surface of a material. To evaluate the conditions for crack spreading, it is necessary to test a specimen under loading in bulk. The suggested procedure involves a bent strip. As bending stresses are known, from the differences in crack length along and across the strip, the resistance of the material surface to crack propagation is determined.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Berka, L., Kopecký, L. and Murafa, N.V. (2003). Preparation and Study of Properties of Cr2O3 Layers. Microscopic Analysis. Workshop 2003-CD ROM, CVUT Prague.

  • Eriksson, C.L., Larson, P.-L. and Rowcliffe, D.J. (2003). Strain-hardening and residual stress effects in plastic zones around indentations. Elsevier-J. of Mater. Sci. and Eng. A340, 193-203.

    Google Scholar 

  • Houdková, Š., Enžl, R. and Bláhová, O. (2003). On Indentation Fracture Toughness of Sprayed Coatings. (In Czech). Vrstvy a povlaky, Proceedings, DIGITAL GRAPHIC Trenčín. Vydání 2, 87-92.

    Google Scholar 

  • Larson, Per-Lennart and Giannakopoulos, A.E. (1998). Tensile stresses and their application to cracking at pyramid indentation of pressure — sensitive hard metals and ceramics. Elsevier-J. of Mater. Sci. and Eng. A254, 268-281.

    Google Scholar 

  • Liebowitz, H. (1969). Fracture, Vol. II., Ch. 3., p. 233.

    Google Scholar 

  • Murakami, Y. (1990). Russian transl. Stress Intensity Factors Handbook, Vol. 1., p. 201, MIR, Moscow.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Berka, L., Murafa, N. On the estimation of the toughness of surface microcracks. International Journal of Fracture 128, 115–120 (2004). https://doi.org/10.1023/B:FRAC.0000040973.14787.82

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/B:FRAC.0000040973.14787.82

Navigation