SINGLE-FIBER MICROBUCKLING IN A MODEL COMPOSITE

Fiber microbuckling, a compressive failure mechanism in unidirectional fiber-reinforced composites, was studied in a model system composed o f a single polyamide fiber in a silicone matrix. The transparent matri x permitted direct observation of fiber microbuckling during compressi on. In all instances the shape of the microbuckling was planar and sin usoidal. The effects of fiber diameter, fiber modulus, and matrix modu lus on the critical wavelength were observed. Excellent agreement with predictions from the stability analyses of Sadowsky et al. and Darby and Kanellopoulos was obtained.