An evaluation of multiaxial fatigue life assessment methods for engineering components

This article deals with the problem of multiaxial fatigue life assessment of engineering components. General aspects of the critical plane damage models are discussed first. A computer-based procedure for multiaxial fatigue life assessment incorporating critical plane damage models, suitable for use in design evaluations of engineering components based on finite element analysis results, is presented and applied to correlate results from tests conducted on SAE 1045 steel notched shaft specimens. From experimental data correlations, it is found that the second variant of the critical plane models (in which critical planes are defined as the planes experiencing the maximum damage) provides better life estimates than the first variant (in which critical planes are defined as the planes experiencing the maximum range of strain) or the conventional local strain based life prediction method, even for simple and short loading histories made up of repeating cycles. (C) 1999 Elsevier Science Ltd. All rights reserved.