Comparison between whiskers and filaments and their use in fibre-reinforced materials

Abstract

Whiskers and high-strength filaments as potential reinforcing materials differ in their proper­ties. Their applicability in fibre-reinforced composites depends on these properties. The short­ness of the whiskers, the large scatter of their strength and their high price involve difficulties for their use in composites. The more advantageous geometry of continuously produced filaments, their relatively low price and their good processing qualities favour the use of quasi-endless filaments as reinforcing material. The latter holds especially for the production of rotationally symmetric shaped parts, where the 'filament-winding technique' is applied. But even parts which are not rotationally symmetric can be produced by this technique if it is used as an intermediate stage of shaping. This method has been applied to produce filament-reinforced shaped parts with plastics, light-metal, heavy-metal and glass matrices. As filamentary reinforcing materials fine steel wire is preferably used; some others are produced by the improved Taylor method. The strength values measured on the composites amount to a multiple of the strength of the matrix material and are in satisfactory agreement with theory.