Damage characterization of elastomeric composites using X-ray attenuation

X ray tomography is specially suitable to study damage of composites in 3D and with X ray attenuation. The first results from our laboratory were published in ASTM/STP 1128 on 1992 and in ASME Vol.43 on 1994. This new paper is devoted at elastomeric composites based on natural rubber reinforced with carbon, black Using X ray scanner it is shown that: the attenuation of X ray is correlated with the molecular structure, amorphous or crystallite phases. With an in situ tensile test, initiation of crystallization is detected. when a specimen in rubber is submitted at a compression fatigue loading the damage appears inside the specimen where the maximum shear located. The X ray tomography is able to detected the first damage and the crack growth inside the specimen. The damage crack is successfully compared with numerical simulation of the stress field in compression. Finally, the role of crystallization in shear before damage is shown by means of X ray attenuation. All together, X ray tomography is shown to be an accurate tool to study molecular arrangement, reinforcement repartition, molecular transformation until damage and cracking in elastomeric matrix composite material, at mesoscopic scale.