Effective maximum tensile stress and strain for industrial fatigue design of rubber products made from filled NR and SBR.

This article focuses on the development and validation of two novel fatigue damage criteria—effective maximum tensile stress and effective maximum tensile strain—for predicting the fatigue life of rubber antivibration products under various R ratios (the ratio of minimum to maximum stress/strain). These criteria, which do not require adjustable parameters, were tested using published experimental data from three types of rubber specimens: cylindrical dumbbell samples made from filled natural rubber (NR) and AE42 and AE2 samples made from filled styrene-butadiene rubber (SBR). The results demonstrated strong correlations (R² up to 0.91) between predicted and observed fatigue lives across approximately 200 loading cases, including tension, torsion, and combined loads, with crack locations consistently aligning with maximum values of the proposed criteria. The approach enables direct visualization of fatigue-critical areas without additional software costs, offering a practical, cost-effective tool for design engineers and manufacturers to optimize rubber product fatigue performance using standard test samples and equipment.