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Design-Oriented Degradation Mapping and Hyperelastic Model-Switch Guidelines for Nitrile-Butadiene Rubber Seals.
Na-Yeon Choi1,2, Dong-Seok Kim3, Sung-Uk Zhang1,2
1Digital Twin Laboratory, Dong-Eui University, 176 Eomgwang-ro, Busan 47340, Republic of Korea.
Polymers
|September 13, 2025
Summary
This study provides a guideline for selecting hyperelastic models for nitrile-butadiene rubber (NBR) seals based on their thermal degradation state. It enables more accurate stress predictions for automotive and energy applications.
Area of Science:
- Materials Science
- Mechanical Engineering
- Polymer Science
Background:
- Nitrile-butadiene rubber (NBR) seals degrade mechanically at high temperatures.
- A clear method for choosing hyperelastic models based on NBR degradation is lacking.
Purpose of the Study:
- To develop a quantitative guideline for switching between hyperelastic models for NBR seals undergoing thermal aging.
- To improve the accuracy of stress predictions for NBR seals in demanding applications.
Main Methods:
- Accelerated thermal aging tests combined with Flynn-Wall-Ozawa analysis to estimate activation energy.
- Arrhenius-based equivalence to link aging tests to service conditions.
- Tensile testing, dynamic mechanical analysis, thermogravimetric analysis, and finite element simulations with L2-norm benchmarking.
Main Results:
- A degradation map and model-switching guideline were established.
- The Neo-Hookean model is suitable for less-embrittled NBR.
- The five-parameter Mooney-Rivlin model is recommended for more embrittled NBR.
Conclusions:
- The proposed framework enhances stress-prediction fidelity for aged NBR seals.
- Model complexity is matched to the aging state, optimizing design efficiency.
- Facilitates faster and more reliable design of NBR seals for high-temperature automotive and renewable energy sectors.
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