Nondestructive Detection of Fiber Waviness in Laminates

The Numerical Technology Company and North Star Imaging (NSI) team in this project to develop and verify a Computed Tomography (CT) based technology for accurate three-dimensional measurement and characterization of fiber waviness (wrinkles) in fiberglass/epoxy and carbon/epoxy composite structures. This team is supported by Bell Helicopter Textron who will provide the composite structures for the technology verification. The nondestructive evaluation (NDE) technology will enable: (a) ability to measure wrinkles and porosity in large structures and thick parts such as spars and yokes; and (b) automated three-dimensional wrinkle characterization. Wrinkles and porosity defects as well as their combinations contribute to structural failure. Ability to capture the shape of small wrinkles embedded deep inside a thick glass/epoxy structure as well as detect multiple wrinkles through the thickness will be verified. As wrinkle geometry and porosity distributions in the fatigue-critical composite parts are three-dimensional, accurate 3D measurement ability will be developed. The defect measurements will also converted into 3D finite element models for assessment of effects of the manufacturing defects on structural performance.