STP873: Use of X-radiographic Tracers to Measure Fiber Orientation in Short Fiber Composites

    Denton, DL
    Research and Development Division, Owens-Corning Fiberglas Corp., Technical Center, Granville, OH

    Munson-McGee, SH
    Research and Development Division, Owens-Corning Fiberglas Corp., Technical Center, Granville, OH

    Pages: 13    Published: Jan 1985


    Abstract

    The degree of fiber orientation is a major factor in determining the mechanical behavior of short fiber composites. A method to determine fiber orientation in short fiber composites such as sheet molding compound (SMC) is presented. A small amount of glass fibers with a high lead content is incorporated into the composite as a tracer. The lead glass tracer fibers mimic the orientation changes that occur during processing. X-radiographs of composites containing the lead glass fibers provide clear, high contrast images of the tracer fibers. Analysis of the X-radiographic image by Fraunhofer light diffraction provides a quantification of the degree of fiber orientation in the composite. Results of fiber orientation and mechanical property measurements for SMC composites molded with different amounts of flow are presented. These techniques are potentially useful for research on fiber orientation, development of prototype parts, optimization of molding conditions, and production quality control.

    Keywords:

    short fiber composites, short fiber orientation, X-radiography, Fraunhofer light diffraction, sheet molding compound, glass fibers, tracer fibers, compression molding, injection molding, reaction injection molding, transfer molding, nondestructive evaluation


    Paper ID: STP34012S

    Committee/Subcommittee: D30.08

    DOI: 10.1520/STP34012S


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