Determination of Damage Parameters for Microcrack Formation: Measurement and Application in Lifetime Prediction Models

  • H. Stamm
  • P. Hähner
  • J. Schwertel
Conference paper


Under creep conditions, e.g. in pressurised components operating at high temperatures, the microstructural degradation of materials manifests itself in the formation of cavities and microcracks on the grain boundaries. The knowledge of the evolution of this microstructural damage is essential for the reliable assessment of the residual service life. Lifetime prediction usually involves the structural analysis by numerical methods such as the finite element method. Constitutive models describing the macroscopic materials behaviour are then needed in which this type of degradation is taken into account by damage variables defined on a macroscopic scale.


Ultrasonic Velocity Rupture Surface Damage Parameter Damage Variable Creep Damage 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • H. Stamm
    • 1
  • P. Hähner
    • 1
  • J. Schwertel
    • 1
  1. 1.European CommissionJoint Research CentreIspraItaly

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