TEST AND CALCULATION OF THE CARBON BLACK REINFORCEMENT EFFECT ON THE HYPER-ELASTIC PROPERTIES OF TIRE RUBBERS

Abstract

ABSTRACT The strong reinforcement effect of filler particles on the mechanical behavior of elastomers has been well known for decades and has significantly contributed to the wide use of rubber materials in the tire industry. By using the automated grid method testing system, the quasi-static mechanical tests of three typical kinds of carbon black–filled tire rubbers with different elastomeric matrixes are carried out. Then, the influences of carbon black reinforcement on their hyper-elastic properties (the stress–strain relationship, the “S”-shaped nonlinear characteristic, and the stress level at certain stretch) are systemically discussed. The experimental data also allowed for a direct evaluation on a classical constitutive model based on the amplification of the first strain invariant. Comparison results illustrate that this model can explicitly take into account the reinforcement dependence of hyper-elasticity of tire rubbers in a certain degree. After that, the moderate finite deformation of these reinforced tire rubbers is studied using numerical investigations. For gaining the effect of particle clustering, different spatial distributions of carbon black particles (regular random dispersion and agglomerate random dispersion) in the elastomeric matrix are analyzed through the finite element simulations. The comparison of experimental and numerical results emphasizes the importance of the consideration of particle distribution and suggests that successful modeling of the material mainly requires a rational treatment of composite nature of its microstructure.