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Abstract

An investigation of the kinetics of fatigue crack growth in a random short-fiber rein forced SMC composite is presented. Experiments were conducted on notched SMC- R50 composite specimens subjected to cyclic uniaxial tensile and mixed-mode fatigue loading. Fatigue crack propagation rates were studied in terms of fracture mechanics parameters. A power-law relationship between the crack growth rate and the cyclic stress intensity factor range was obtained for the SMC-R50 composite under various fatigue loading modes. The value of the exponent in the power-law equation was found to be much higher for the composite than values reported for metals and some structural polymers. A fractographic study of fatigue fracture surfaces was also con ducted. Mechanisms of fatigue crack growth in the SMC-R50 composite were iden tified. A mechanical model is then proposed for further study of the mechanics of fatigue crack growth in random short-fiber SMC composites.

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Fatigue Crack Propagation in Random Short-Fiber SMC Composite

Abstract

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