In-situ SEM study of fatigue crack growth mechanism in carbon black-filled natural rubber

International audienceA micro-tensile testing machine placed in the chamber of a scanning electron microscope is used to perform in-situ fatigue tests on a 43 phr carbon black-filled cis-1,4-polyisoprene rubber; the crack tip is observed in realtime during crack propagation. These observations lead to a detailed description of the crack tip morphology, to the understanding of the fatigue crack growth mechanism and to the microstructural explanation of crack branching phenomenon. Finally these results are related to the great fatigue properties of natural rubber and to strain-induced crystallization