Mechanical Modeling of Irradiation Creep and its Application to the Analysis of Creep Crack Growth

  • S. Murakami
  • M. Mizuno
Conference paper
Part of the International Union of Theoretical and Applied Mechanics book series (IUTAM)


After discussing the mechanisms and the physical theories of neutron irradiation reported so far, a constitutive model of irradiation creep, swelling and irradiation creep damage applicable to the inelastic analysis of nuclear reactor components was developed. It was assumed that the irradiation creep can be decomposed into irradiation-induced creep and irradiation-enhanced creep. By taking account of the physical mechanisms, the irradiation-induced creep was represented by an isotropic tensor function of order zero and one with respect to stress, as well as of neutron flux and neutron fluence. The volumetric part of the irradiation-induced creep was identified with swelling. The irradiation-enhanced creep was described by modifying Kachanov-Rabotnov creep damage theory by incorporating the effect of irradiation. The utility of the proposed constitutive equation was demonstrated by analyzing the irradiation creep and irradiation creep damage of type 316 stainless steel. As an application of the proposed equations, creep crack growth in an infinite plate under neutron irradiation was analyzed. A double cantilever beam model combined with continuum damage mechanics was employed to simplify the analysis. The effects of neutron irradiation on the rate of steady-state creep crack growth and the distributions of stress, strain and damage in front of the crack tip were discussed.


Constitutive Equation Creep Rate Neutron Irradiation Neutron Fluence Creep Damage 
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Copyright information

© Springer-Verlag, Berlin Heidelberg 1991

Authors and Affiliations

  • S. Murakami
    • 1
  • M. Mizuno
    • 1
  1. 1.Department of Mechanical EngineeringNagoya UniversityChikusa-ku, NagoyaJapan

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