Defect Structure of WC Deformed at Room and High Temperatures

  • M. K. Hibbs
  • R. Sinclair
  • D. J. Rowcliffe


Single crystals of WC, deformed by micro-indentation at room temperature and at 1000°C, are examined by transmission electron microscopy in order to determine the mechanism of slip. The plastic deformation induced by indentation occurs by the motion of partial dislocations with Burgers vectors 1/6 \( \left\langle {11\bar 23} \right\rangle \). These partial dislocations combine in pairs to form extended dislocations with Burgers vectors 1/3 \( \left\langle {11\bar 23} \right\rangle \). Deformation in samples indented at 1000°C takes place by the same mechanism.

Reactions occur between the leading partial dislocations of faults on intersecting slip planes. The new partial dislocation formed at one of these intersections is shown to have Burgers vector 1/6 \( \left[ {1\bar 210} \right] \), This reaction causes the defect configuration to became sessile and may be the first step in a crack nucleation mechanism similar to that proposed by Cottrell for bcc metals. The observation of defect pile-ups at tips of microcracks formed near room temperature, high load (500 gm) indentations, supports this suggestion. A high density of defects found near the cracked edge of a specimen indicates that plastic deformation may accompany crack propagation under some circumstances.


Burger Vector Slip Plane Tungsten Carbide Partial Dislocation Slip Trace 
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  1. 1.
    T. Takahashi and E. J. Freise, Determination of the Slip Systems in Single Crystals of Tungsten Monocarbide, Phil. Mag. ser.8, 12:1 (1965).Google Scholar
  2. 2.
    S. B. Luyckx, Slip System of Tungsten Carbide Crystals at Room Temperature, Acta Metall. 18:233 (1970).CrossRefGoogle Scholar
  3. 3.
    T. Johannesson and B. Lehtinen, The Analysis of Dislocation Structures in Tungsten Carbide by Electron Microscopy, Phil. Mag. 24:1079 (1971).CrossRefGoogle Scholar
  4. 4.
    T. Johannesson and B. Lehtinen, On the Plasticity of Tungsten Carbide, Phys. Stat. Sol. (a) 16:615 (1973).CrossRefGoogle Scholar
  5. 5.
    J. D. Bolton and M. Redington, Plastic Deformation Mechanisms in Tungsten Carbide, J. of Mat. Sci. 15:3150 (1980).CrossRefGoogle Scholar
  6. 6.
    S. Hagege, J. Vicens, G. Nouet, and P. Delavignette, Analysis of Structure Defects in Tungsten Carbide, Phys. Stat. Sol. (a) 61:675 (1980).CrossRefGoogle Scholar
  7. 7.
    M. K. Hibbs and R. Sinclair, Room-Temperature Deformation Mechanisms and the Defect Structure of Tungsten Carbide, Acta Metall. in press (1981).Google Scholar
  8. 8.
    D. J. Rowcliffe, Indentation Deformation of Tungsten Carbide and Tungsten-Titanium Carbide, these proceedings.Google Scholar
  9. 9.
    P. B. Hirsch, A. Howie, R. B. Nicholson, D. W. Pashley, and M. J. VJhelan, “Electron Microscopy of Thin Crystals”, Butterworth, London (1965).Google Scholar
  10. 10.
    A. H. Cottrell, Theory of Brittle Fracture in Steel and Similar Materials, Trans. AIME 212:192 (1958).Google Scholar
  11. 11.
    S. Pattanaik and D. J. Rowcliffe, to be published (1982).Google Scholar
  12. 12.
    B. R. Lawn, B. J. Hockey, and S. M. Wiederhorn, Atomically Sharp Cracks in Brittle Solids: An Electron Microscopy Study, J. of Mat. Sci. 15:1207 (1980).CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1983

Authors and Affiliations

  • M. K. Hibbs
    • 1
  • R. Sinclair
    • 1
  • D. J. Rowcliffe
    • 2
  1. 1.Department of Materials Science and EngineeringStanford UniversityStanfordUSA
  2. 2.SRI InternationalMenlo ParkUSA

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