Journal of Materials Science

, Volume 43, Issue 6, pp 2077–2081 | Cite as

Mode-II shielding-curve of Al2O3 from measurement of cone crack angles

  • Theo FettEmail author
  • Gabriele Rizzi
  • Michael J. Hoffmann
  • Rainer Oberacker
  • Susanne Wagner

Many ceramic materials exhibit the effect of an increasing crack growth resistance during crack extension. Especially in the case of coarse-grained materials, cracks generally follow the grain boundaries, leave the original crack plane and produce a crack-face roughness. In the theoretical analysis forces transmitted by local links between the two crack faces are smoothed and replaced by so-called continuous bridging stresses acting against the crack opening. As the consequence of such bridging stresses, there exists a shielding stress intensity factor term that shields the crack tip partially from the applied loads. This effect as a reason for the occurrence of R-curves is well documented in literature for cracks under pure mode-I loading conditions [1].

In addition it has to be expected that crack-face interactions will also affect crack extension under pure or superimposed mode-II loading as for instance outlined in literature for frictional crack-face interactions [2, 3, 4]. In [5]...


Stress Intensity Factor Crack Length Cone Angle Shear Traction Applied Stress Intensity Factor 


  1. 1.
    Munz D (2007) J Am Ceram Soc 90:1CrossRefGoogle Scholar
  2. 2.
    Mendelsohn DA, Gross TS, Zhang Y (1995) Acta metall mater 43(3):893CrossRefGoogle Scholar
  3. 3.
    Mendelsohn DA, Gross TS, Goulet RU, Zhouc M (1998) Mater Sci Eng A249:1CrossRefGoogle Scholar
  4. 4.
    Lathabai S, Rödel J, Lawn BR (1991) J Am Ceram Soc 74:1340CrossRefGoogle Scholar
  5. 5.
    Fett T, Rizzi G, Munz D, Hoffmann M, Oberacker R, Wagner S (2006) J Ceram Soc Jpn 114:1038CrossRefGoogle Scholar
  6. 6.
    Rice JR (1972) Int J Solids Struct 8:751CrossRefGoogle Scholar
  7. 7.
    Munz D, Fett T (1999) CERAMICS, failure, material selection, design. Springer-Verlag, HeidelbergGoogle Scholar
  8. 8.
    Cotterell B, Rice JR (1980) Int J Fract 16:155CrossRefGoogle Scholar
  9. 9.
    Fett T, Rizzi G, Munz D, Badenheim D, Oberacker R (2006) Fatigue Fract Eng Mater Struct 29:867CrossRefGoogle Scholar
  10. 10.
    Kounga Njiwa AB, Yousef GS, Fett T, Rödel J (2005) Eng Fract Mech 72:1011CrossRefGoogle Scholar
  11. 11.
    Fett T, Munz D, Thun G, Bahr HA (1995) J Amer Ceram Soc 78:949CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Theo Fett
    • 1
    • 2
    Email author
  • Gabriele Rizzi
    • 1
  • Michael J. Hoffmann
    • 2
  • Rainer Oberacker
    • 2
  • Susanne Wagner
    • 2
  1. 1.Institut für Materialforschung IIForschungszentrum KarlsruheKarlsruheGermany
  2. 2.Institut für Keramik im MaschinenbauUniversität KarlsruheKarlsruheGermany

Personalised recommendations