Prediction Accuracy of Hyperelastic Material Models for Rubber Bumper under Compressive Load

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Mechanics

Background:

• Hyperelastic material models like Mooney-Rivlin, Yeoh, Gent, Arruda-Boyce, and Ogden can model rubber's stress-strain behavior under various loads.
• Characterizing rubber for product design often involves extensive testing under uniaxial and biaxial tension, and pure shear conditions.

Purpose of the Study:

• To evaluate the effectiveness of different hyperelastic models in predicting rubber behavior under compression, specifically for rubber bumpers.
• To determine if simplified laboratory testing using only uniaxial compression data can adequately inform material model selection for product design.
• To assess the accuracy of these models in finite element analysis of complex rubber product geometries.

Main Methods:

• Fitting various hyperelastic material models (Mooney-Rivlin, Yeoh, Gent, Arruda-Boyce, Ogden) using stress-strain data from uniaxial compression tests of rubber samples.
• Conducting laboratory and numerical tests on a rubber bumper with a defined compound and complex geometry.
• Implementing finite element analysis (FEA) to model the rubber bumper's behavior, considering material nonlinearity and large deformations.

Main Results:

• The Yeoh hyperelastic material model demonstrated superior performance in predicting the rubber product's response under compressive load and complex strain states when fitted with uniaxial compression data only.
• Using solely uniaxial compression test data for model fitting significantly reduces laboratory testing time compared to traditional multi-axial methods.
• The study highlighted the importance of considering numerical discretization and nonlinear behaviors in the finite element analysis of rubber products.

Conclusions:

• The Yeoh model is the most suitable hyperelastic model for accurately predicting rubber bumper performance when material characterization is limited to uniaxial compression tests.
• Simplified material testing protocols based on uniaxial compression can be sufficient for designing rubber products, leading to more efficient development cycles.
• Accurate finite element analysis of rubber components necessitates careful consideration of material models and numerical simulation strategies, especially for complex geometries and nonlinear material responses.