High-precision numerical simulation method for thermal-mechanical coupling in rubbers

Improving the precision of numerical simulations in thermal-mechanical coupling for amorphous polymer materials is crucial for their effective utilization. To enhance the precision of rubber numerical simulations, this study proposed a method considering the temperature and strain rate to establish tensile testing conditions based on the principle of time-temperature equivalence. Additionally, to obtain more precise parameters for hyperelastic constitutive equations, stress relaxation experiments were conducted to determine a set of stress values under complete rubber stress relaxation, which were used to fit the hyperelastic components of the hyper-viscoelastic algorithm. A finite element model of rubber rebound was established, and a hyperelastic model based on loss factor and a hyperelastic model based on Prony series (hyper-viscoelastic) were used to calculate the temperature changes caused by rubber rebound coefficient and energy dissipation during the rebound process at 110, 120, and 130 degrees C. We compared the calculation results of these two algorithms with experimental data to verify their accuracy. The research results show that the average error of the rebound coefficient of the hyperelastic algorithm at three temperatures is 3.63%, and the average error of the rebound coefficient of the hyper-viscoelastic algorithm at these three temperatures is 0.93%. The comparison with the rebound test results shows that the hyper-viscoelastic method is more accurate and better captures the viscoelastic hysteresis of rubber, but the model calculation time is longer. In addition, at the moment of rebound sample impact, the maximum temperature rise amplitude of the hyperelastic algorithm sample impact position is 2.60, 1.75, and 0.91 degrees C, which are 110, 120, and 130 degrees C, respectively; The maximum heating amplitudes of the hyper-viscoelastic algorithm are 2.05, 1.35, and 0.61 degrees C. The hyper-viscoelastic algorithm is closer to the actual test results.Highlights Applied the principle of time-temperature equivalence. Determination of material parameters using the hyper-viscoelastic algorithm. Calculated the temperature change during the rubber rebound process.