NON-ISOTHERMAL STAMP FORMING OF CARBON/POLYAMIDE 12 BASED COMPOSITES

摘要

Stamp forming of thermoplastic composite materials offers the potential for rapid processing of shell-like components. The highly non-isothermal process is suited to a variety of thermoplastic composite precursor materials, ranging from unconsolidated commingled yarns to fully impregnated products. Two novel carbon fiber weave reinforced polyamide 12 systems have been studied, comprising a commingled yarn system, with varying degrees of preconsolidation, and sheets impregnated via reactive processing. Prediction of the consolidation quality for the commingled yarn system, in terms of residual void content, has been made by coupling a heat transfer model to a consolidation model, verified by porosity measurements for different stamp forming conditions. The potential of continuous impregnated sheet production has been demonstrated via reactive line impregnation (pultrusion) of UD profiles with anionically polymerized laurolactam. Larger plaques were produced for non-isothermal stamping trials where carbon fiber weaves were impregnated with laurolactam via a thermoplastic RTM method. Stamp forming trials have demonstrated the feasibility of these two materials forms.