The influence of distribution between fibre orientations upon the thermal expansion characteristics of carbon fibre-reinforced plastics

The linear thermal expansion coefficients of nine laminates of carbon fibre-reinforced plastic containing fibres angled at 0°, ± 45° and 90° to the measurement direction in proportions from 0% to 100%, and of the matrix resin Fibredux 914C, have been measured between approximately −200°C and +200°C. Predicted values for bidirectional and tridirectional laminates from unidirectional data agree well with experimental values for (0°, 90°) and (± 45°, 90°) laminates. The thermal expansions of these composites are more dependent upon thermal history than those of similar composites based upon ERLA 4617/m PDA, DLS 351/BF 3 400 and Code 69 resins, particularly at higher temperatures in the more highly internally stressed directions.