Manufacture of Powder-Impregnated Thermoplastic Composites

Abstract

The use of thermoplastic composites has been limited by the lack of reliable techniques to make prepregs of consistent quality. Dry powder impregnation methods offer a new approach to the solution of this problem. This paper discusses the features that are essential to the development of an acceptable dry powder process The physical principles that govern the manufacture of thermoplastic prepreg tapes of controllable fiber-matrix volume fractions and the consolidation of these tapes to make void-free composite parts are presented A novel powder prepregging process suitable for the manufacture of high-quality powder-impregnated tapes and their subsequent consolidation to make void-free parts is discussed. It is shown that a well-designed dry powder process can achieve fine control over both fiber-matrix composition in the prepreg tape and intimate wetting between in dividual fibers and the thermoplastic matrix Powder prepreg tapes can be consolidated into void-free specimens with simple consolidation cycles developed for a specific fiber- matrix combination