Multiaxial notch fatigue life prediction based on the dominated loading
modes under variable amplitude loading
Abstract
An innovative computational methodology is proposed for fatigue life
estimation of notched components subjected to multiaxial variable
amplitude loadings. In the proposed methodology, if the calculated
uniaxial fatigue damage by axial tension‐compression loading path is
more than that by the pure torsional loading path, an axial strain-based
multiaxial fatigue damage parameter is selected to compute multiaxial
fatigue damage, or else a shear strain-based multiaxial fatigue damage
parameter is selected to compute multiaxial fatigue damage. Moreover,
the proposed methodology utilizes axial strain-based and shear
strain-based multiaxial fatigue damage parameters in replacement of
equivalent strain amplitude to take into consideration of the
non-proportional additional hardening phenomenon. The fatigue data of
7050-T7451 aluminum alloy and GH4169 superalloy notched specimens are
utilized to verify the proposed notch fatigue life prediction
methodology, and the prediction results are satisfactory.