HEAT BUILD-UP OF RUBBER UNDER CYCLIC LOADINGS: VALIDATION OF AN EFFICIENT DEMARCH TO PREDICT THE TEMPERATURE FIELDS

Abstract

ABSTRACT Rubber-like materials exhibit a hysteretic behavior under cyclic loadings that, combined with a very low thermal conductivity, leads to a temperature rise called heat build-up in the literature. This phenomenon is especially crucial for antivibration parts that require both good fatigue resistance and high damping properties, involving a high dissipation under cyclic loading. Moreover, these parts exhibit complex shapes leading to complex local mechanical fields and therefore to thermal sources and temperature fields difficult to predict. To overcome the difficulties of the classical approach based on thermodynamically based models and to provide acceptable characterization and computation times for industrial needs, a simple phenomenological approach was previously suggested. We aim at validating this approach for several case studies. First, an identification procedure is proposed to identify efficiently the parameters of the thermal and mechanical problems, from a single test on an hourglass-shaped specimen. The validity of the identification step and of the modeling is then challenged by the confrontation of the numerical predictions to the results of an extended experimental database. The influences of the main influent factors are investigated (displacement amplitude, frequency, load ratio, sample volume) for tension and torsion tests on hourglass-shaped samples. The validity of the approach is asserted both on transient and stabilized temperature fields, for a temperature rise lower than 20 °C.