Fibre Composites Available to Purchase

PRE‐EMINENT in the manufacture of fibre‐reinforced composites for general use and in these particular applications, for aerospace purposes, the CIBA‐Geigy company has circulated information regarding the many types of matrix resins, fibres and processes that are used in their production. An evaluation of the particular fibre/resin/processing combination that is best for a defined task may be accomplished by means of polymer selection (i.e. the range of available materials) and following this, a more detailed consideration of the matrix aspects of processing. Matrix resins are generally divided into thermoplastics and thermosets and the following could be considered representative of the first of these: nylon polyetheretherketone (PEEK), polybutylene terephthalate, polycarbonate, polyethylene, polysulphone. Typical thermosets could be epoxy, melamine, phenolic, polyester, polyimide, and ureas. Reinforcing fibres may be natural, synthetic organic or inorganic such as sisal, flax, nylon, glass, aramid, carbon, boron, alumina and silicon carbide and the fibres may be employed as short lengths or continuous filaments. They can be used as appropriate to the type of application and presented in prepreg form in various ways such as unidirectional (UD) continuous filament tape, aligned UD short filament, woven fabrics or papers, or as injection and compression moulding compounds. To form these prepregs into finished parts, the most commonly used processes are autoclave moulding, press and matched tool moulding, compression, injection, vac‐bag and expanding rubber moulding, filament winding and pultrusion.