Analysis of an image processing method for fiber orientation in polymer composites

The errors in fiber orientation distribution measurements of compression molding materials have been investigated, for generated as well as for real distributions. Because of the size of the sample, only a finite number of fibers are visible in a picture leading to a statistical error in the measurement. A method is proposed to express this error as function of the number of visible fibers and the number of subintervals the distribution is divided into. Studies of the error in a Fraunhofer/FT based fiber orientation distribution analysis have been performed, including effects of increasing number of fibers (fiber-fiber intersections) in generated pictures and investigation of the errors in real fiber images. All steps in a fiber orientation distribution analysis of SMC/GMT kind of material are described, including suitable equipment, image enhancement methods and investigation of the errors present in analysis of a real image as well as comparisons to hand-measured data.