Multiaxial fatigue space: A three-dimensional space constituted of fatigue basic units

Resumen:
In this article, multiaxial fatigue space, fatigue basic unit and fatigue damage map are proposed, as well as out-of phase failure angle and out-of-phase level coefficient. The comprehensive discussion of out-of-phase failure is conducted, it is found that the relative distortion deformation is a proper reflection for out-of-phase failure and it has a limit effect. The validation with 394 samples of 13 materials under 37 loading conditions indicates that the proposed theory has an excellent universal capability with minimum prediction error and favorable error distribution, the prediction ability is improved by 21.1% compared with original Lu criterion.