The Effect of Interface Damage on the Microbuckling of Unidirectional Fiber-Reinforced Composites

Fiber microbuckling is the primary failure mechanism in unidirectional fiber-reinforced composites under compression. Due to processing or service conditions, damage (e.g., microsacks) exists at fiber/matrix interfaces. The effect of damage on the microbuckling of fibers is investigated in the present study. Based on the micromechanics analysis, the damage at interfaces is modeled as a linear spring against interface sliding, and the spring constant depends on the damage level. It is established that the critical strain for fiber microbuckling is relatively insensitive to the interface damage, but increase rapidly with the fiber volume fraction.