A mathematical model of the hot-pressing consolidation process for manufacturing a multi-layered oriented strand composite is developed and tested. Such a process model requires independent physical properties and user-specified structure for each layer of the mat. The model uses two-dimensional (slow variation is assumed in the third dimension) heat- and mass-transfer theory and a viscoelastic compression model. The through-the-thickness (vertical) density profile (VDP) was found to be highly dependent on the initial moisture content gradient, internal mat strand properties, and hydrothermal compressive response of the mat. The VDP predicted by the model showed good agreement with experimental results. The proposed mathematical model thus shows promise as a tool to analyze optimally design-oriented strand composites.
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