This topic has one session with 5 papers which represent a good mixture of experimental and theoretical results. The first two papers by Herter et al present experimental data to show if the fatigue behavior of austenitic material in cladding and in dissimilar metal welds conforms to the fatigue curve obtained for the corresponding austenitic base material. This is an important question in the fatigue evaluation of reactor components. The third paper by Nakamura, Oguma and Nukaya determines the strain rate effect in an air environment under high cycle conditions at different levels of mean stress. Interestingly, the strain rate effect depended on the mean stress which affected fatigue crack growth patterns. The fourth paper by Kalnins, Rudolph and Willuweit discusses the use of Chaboche's nonlinear kinematic hardening model for ratcheting simulations. The paper describes methods to obtain a representation of the stress-strain needed for such simulations. The final paper by Lidonnici shows the derivation and application of a simplified fatigue assessment method for base metal and welded components. The method is contained in the European EN12445 standard and allows a fast, conservative estimation of the fatigue usage factor.
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