Microstructure and mechanical property of short carbon fiber reinforced injection-moulded PEEK composites

Experimental results proved that submicrostructure existed in short carbon fiber reinforced injection-moulded polyether ether ketone (PEEK) composites. The thicknesses of the skin and core layers could be characterized by the metallographic optical microscope. Mechanical properties of the full plate could be calculated by the rule-of-mixture approach, in which the separately determined tensile strengths and elastic modulus of the skin and core layers were combined with regard to their relative contribution to the full thickness of the original sample. The great thermo-stress and anisotropic mechanical properties between the skin and core layers resulted from different fiber orientations and PEEK crystallinities. Therefore, the correlation of submicrostructure and mechanical properties of the skin and core layers with the processing condition and mould configurations became one of the most important works for the product design for short fiber reinforced injection-moulded plastics composites.