THE EFFECT OF GLASS FIBER LENGTH ON ORIENTATION DISTRIBUTION WITHIN CENTER AND END GATED INJECTION MOLDED COMPOSITES

In this paper, the Method of Ellipses has been applied to both short and long fiber polymer composites in order to evaluate the effect of fiber length on experimental orientation distribution. The resulting fiber orientation distributions for both short and long fiber-reinforced composites have subsequently been compared at multiple percentages of mold fill for the same geometry, including near the entry region of the mold. Preliminary data suggests that an increase from short (<1 mm) to long (>1 mm) fibers results in increased transverse fiber alignment in both the center-gated disc and along the center-line of the end-gated plaque. Furthermore, preliminary results from the end-gated geometry will be compared to data obtained from the center-gated disc, in order to evaluate the effect of the more complex, 3-dimensional flow field found within the end-gated system.

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