Mechanics of Time-Dependent Materials

, Volume 16, Issue 1, pp 105–115 | Cite as

Study of the PENT test conditions for reducing failure times in high-resistance polyethylene resins for pipe applications

  • Carlos Domínguez
  • Rafael A. García
  • Marcelo Aroca
  • Alicia Carrero
Article

Abstract

A thorough study of the physical conditions in the Pennsylvania Edge Notch Tensile (PENT) test, such as stress and temperature, is carried out in order to reduce the long test times observed in new bimodal and multimodal polyethylene grades (third and fourth generation grades) which may withstand hundreds or thousands of hours at the standard conditions (80C, 2.4 MPa). The results show how on increasing the temperature up to 90C and the applied stress up to 2.8 MPa, the failure time may be reduced by a factor of 6. Special attention should be paid to the n and Q parameters of the Brown and Lu equation, because variations in those parameters could dramatically change the result of the comparison between different systems depending on the temperature and stress value.

Keywords

PENT test Slow crack growth Polyethylene Failure time reduction Pipe material 

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Copyright information

© Springer Science+Business Media, B. V. 2011

Authors and Affiliations

  • Carlos Domínguez
    • 1
  • Rafael A. García
    • 1
  • Marcelo Aroca
    • 2
  • Alicia Carrero
    • 1
  1. 1.LATEP-GIQA, Departamento de Tecnología Química y Ambiental, ESCETUniversidad Rey Juan CarlosMadridSpain
  2. 2.Centro de Tecnología REPSOLMadridSpain

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