Papers by Keyword: Fibre Misalignment

Abstract: This paper investigates the effect of nanosilica on the fibre waviness or misalignment angle distribution of carbon fibre reinforced polymer composite unidirectional laminates. The quality of the laminates was evaluated using image analyzer technique. The polished specimens were examined using Polyvar B-met optical microscope and analysed using KSRUN ZEISS software. The effect of 3, 7 and 13 vol.% nanosilica on the fibre misalignment angle distribution was determined. The results showed that, the fabricated laminates have average fibre volume fraction V_f of 42%, low fibre waviness distribution (average φ_o = 2.5^o) and less than 1% void content. This implies that the fabrication technique, which was employed in the current work, successfully produced good quality laminates. The presence of nanosilica results in a narrow fibre angle distribution in the HTS40/828 laminate.

Abstract: The microstructure (i.e., fibre volume fraction, void content, and fibre misalignment) of unidirectional carbon fibre-reinforced polymer (CFRP) composites was optimised by controlling several parameters during manufacture, namely: (i) compressive pressure (0.25~1.25 MPa, in steps of 0.25 MPa), (ii) vacuum pressure (−0.15, −0.20, −0.30, −0.45, and −0.65 MPa), and (iii) holding temperature (100~140 oC, in steps of 10 oC), applied during autoclave curing with the holding time being 30 minutes for all specimens. Optical micrographs captured from cross-sectional, through-the thickness areas, and in-plane areas of the resulting composites were evaluated and analysed in order to describe their microstructural characteristics.