Abstract

This article presents the challenges of conducting fatigue analysis on rubber components due to their nonlinear behaviour, contrasting this with linear superposition methods used in metal fatigue analysis. Traditional linear methods are effective for linear materials, allowing for efficient stress-strain history generation through the scaling of finite element (FE) solutions based on input load histories. However, these methods fail for rubber because of its complex material properties and behaviours.

To address this, the article introduces the Endurica EIE (Efficient Interpolation Engine), a tool designed to generate stress-strain histories when linear superposition is not applicable. This solver uses a discretized load space, where a set of precomputed load cases is created, allowing for interpolation to estimate responses within the map.

The article also compares linear and nonlinear interpolation methods using an automotive sway bar as a case study, demonstrating significant differences in predicted strain responses and fatigue life. The results showed that nonlinear methods provide a more accurate representation of material behaviour, capturing asymmetries and leading to different fatigue life predictions.

In conclusion, the Endurica EIE provides a robust solution for rubber fatigue analysis by efficiently managing nonlinear complexities, thereby enhancing the accuracy and efficiency of fatigue life predictions.