Investigation of the Effect of Part Length on Process-Induced Fiber-Wrinkled Regions in Composite Laminates

Abstract

A detailed survey was conducted of the localized fiber waviness which develops in unidirectional thermoplastic laminates (T300/P1700) in order to determine how part length affects the distribution of fiber waviness. Eleven laminates of varying length were manufactured using identical processing histories. Each plate exhibited discrete wrinkle regions concentrated in the lengthwise center of the part. The amplitude, wavelength, and distribution of these regions were characterized for each plate processed, while penetration depths were studied for sample plates of each length. The results indicate that the waviness severity increases slightly with increasing part length. Furthermore, the major component is in-plane and the waviness frequently penetrates several plys below the surface.