Application of Multiaxial Criteria to Contact Fatigue Assessment of Spur Gears

Abstract

A new methodology for evaluating the effect of contact stresses generated during the meshing of two spur involute gears is hereby proposed. Taking into account modern multiaxial fatigue criteria (usually applied to other kinds of problems), the real load path on the teeth flank and the consequent evolution of the subsurface stresses, this method aims at the assessment of the pitting and spalling limits of gears. The method is proposed for a better comprehension of these phenomena and for the definition of effective surface fatigue limits of case hardened and nitrided gears. The applied multiaxial criteria include both integral and critical plane approaches.