Journal of Materials Science

, Volume 5, Issue 11, pp 925–932 | Cite as

Hypothetical mechanism of crazing in glassy plastics

  • A. N. Gent


Crazing in glassy plastics is attributed to a stress-activated devitrification of a small amount of material at the tip of a chance nick or flaw, to a softer rubbery state. Subsequent cavitation of the softened material is then assumed to take place under the action of the same dilatant stress responsible for its formation. A transition to ductile yielding is proposed to occur when the material in the tip region undergoes large deformations before softening.

The proposed mechanism of crazing is shown to provide quantitative predictions for the magnitude of tensile stress at which crazing occurs, the increase in crazing stress with hydrostatic pressure, the transition at high pressures to a yielding process without crazing, the reduction in crazing stress in the presence of certain liquids and vapours and, to some extent, for the effects of temperature and pre-orientation. These theoretical predictions are found to be in reasonably satisfactory agreement with experiment. In view of the limited number of adjustable parameters in the theory (the principal one being the stress-magnification factor associated with a typical nick or flaw), this general agreement over a wide range of experimental conditions and variables suggests that the proposed mechanism of stress-crazing is basically correct.


Polymer High Pressure Cavitation Tensile Stress Hydrostatic Pressure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Chapman and Hall Ltd. 1970

Authors and Affiliations

  • A. N. Gent
    • 1
  1. 1.Department of Materials, Queen Mary CollegeUniversity of LondonUK

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