A PROBABILISTIC TWO-SCALE MODEL FOR HIGH CYCLE FATIGUE LIFE PREDICTIONS

Cédric Doudard (1) , Sylvain Calloch (1) , Philippe Cugy (2) , André Galtier (2) , François Hild (1)

1 LMT - Laboratoire de Mécanique et Technologie
2 IRSID - IRSID

It is proposed to develop and identify a probabilistic two-scale model for HCF that accounts for the failure of samples but also for the thermal effects during cyclic loadings in a unified framework. The probabilistic model is based on a Poisson point process. Within the weakest link theory, the model corresponds to a Weibull law for the fatigue limits. The thermal effects can be described if one considers the same hypotheses apart from the weakest link assumption. A method of identification is proposed and uses temperature measurements to identify the scatter in an S/N curve. The validation of the model is obtained by predicting S/N curves for different effective volumes of a dual-phase steel.

Mots clés: fatigue limits; microplasticity; thermodynamics; Weibull model

Domaines: Mécanique des matériaux [physics.class-ph]

Cédric Doudard, Sylvain Calloch, Philippe Cugy, André Galtier, François Hild. A PROBABILISTIC TWO-SCALE MODEL FOR HIGH CYCLE FATIGUE LIFE PREDICTIONS. Fatigue and Fracture of Engineering Materials and Structures, 2005, 28, pp.279-288. ⟨10.1111/j.1460-2695.2005.00854.x⟩. ⟨hal-00322496⟩