Response and Optimal Selection of Temperature‐Dependent Damage Parameters for Multiaxial Fatigue Prediction of Rubber Bushings

Abstract

Automotive rubber bushings are subjected to coupled radial and torsional loading and temperature variation. To investigate the temperature‐dependent response of multiaxial fatigue damage parameters, an N60 nitrile butadiene rubber bushing was studied via finite element analysis at 23 °C, 60 °C, and 90 °C. Six damage parameters were extracted at the critical location: engineering strain, logarithmic strain, Green–Lagrange strain, octahedral shear strain, Luo stress, and strain energy density. S–N curves were derived from uniaxial tests, and multiaxial validation was conducted at 23 °C. Strain‐based parameters increase from 14.6% to 27.6% with temperature. Luo stress decreases by 9.4%, while strain energy density increases by 51.6%. Validation shows that Luo stress and logarithmic strain yield relatively high accuracy. Considering temperature sensitivity and accuracy, logarithmic strain is recommended for life assessment under 60–90 °C.