Automotive weatherstrips made of rubber material have nonlinear hyperelastic/viscoelastic properties and it is difficult to design accurately reflecting their properties. Therefore, it is necessary to present a mathematical property model suitable for rubber properties to design the weatherstrip. The purpose of this study is to select the hyperelastic/viscoelastic mathematical model suitable for the material of automotive weatherstrips and to apply the model to the computational analysis to improve the accuracy and reliability of the static and dynamic analysis for door closing.
Uniaxial tensile/compressive tests and DMA (Dynamic Mechanical Analysis) tests were used to construct a mathematical model. Compression tests using a 100 mm weatherstrip sample were also carried out to verify the computational results. The strain of the automotive door weatherstrip was found to be as low as 0.5 or less when the vehicle door was closed through the finite element analysis. Nonlinear finite element analysis results for each model were compared with compressive load deflection (CLD) for single component test results and a suitable material model was selected for low strain range. The viscoelastic property model was also added to the selected model to confirm the stress relaxation over time. When only uniaxial tensile test data were used, the Form model representing viscoelastic in the Prony series was the most suitable model to express the nonlinear behavior of rubber at low strain range.