Low cycle fatigue of welded joints : coupled initiation propagation model

Yazid Madi (1) , Naman Recho , Philippe Matheron (2)

1 CDM - Centre des Matériaux
2 LISN - Laboratoire d'Intégrité des Structures et de Normalisation

This paper deals with the low-cycle fatigue (LCF) design of welded structures, the aim being the critical analysis of the rule used in the RCC-MR [Design and construction rules for mechanical components of FBR nuclear islands, AFCEN, 1993], for the design and construction of fast breeder reactors. The study takes into account the evolution of the material behavior laws and damage accumulation during the fatigue loading. The adopted model consists of analyzing separately the behavior and the damage evolutions. It allows us to determine the damage ratio corresponding to initiation and propagation of a significant crack in order to determine the life duration. This model suggests the existence of a threshold level of loading, above which micro-cracks initiate. The initiation fatigue life can then be neglected below the threshold level. This work shows also that the RCC-MR rules are valid below this threshold load level.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Yazid Madi, Naman Recho, Philippe Matheron. Low cycle fatigue of welded joints : coupled initiation propagation model. Nuclear Engineering and Design, 2004, 228, pp.179-194. ⟨10.1016/j.nucengdes.2003.06.017⟩. ⟨hal-00166079⟩