COMPRESSION MOULDING OF DISCONTINUOUS-FIBRE CARBON/PEEK COMPOSITES: STUDY OF MECHANICAL PROPERTIES

摘要

A new multi-disciplinary study is being conducted to systematically evaluate, characterize and model the moulding process and mechanical properties of composites manufactured from randomly-oriented carbon/PEEK chopped strips. The heterogeneous meso-structure of this material is expected to give rise to unique material behaviour, which is not entirely accounted for in the current ASTM standards for mechanical testing. This paper presents results of a sensitivity study aimed to evaluate the dependence of measured properties on the size of the coupon gauge section. Coupons of different widths (12.5 - 50 mm) were cut from compression moulded flat panels of randomly oriented chopped strips 25 mm in length and were subjected to quasi-static tensile loading. Results did not show any noticeable effect of the coupon width on the measured properties. Tensile strength and stiffness were found to be substantially lower than those of quasi-isotropic continuous fiber laminates, 59 percent and 26 percent lower, respectively.