Characterization of crystallites in carbon fibres by wide-angle X-ray diffraction

The wide-angle X-ray diffraction patterns of carbon fibres are strongly modulated by disorder in the stacking of carbon layers, preferred orientation and the measuring conditions. A method has been developed to characterize the crystallites in carbon fibres by applying the theory on the wide-angle X-ray diffraction of materials comprising. layer-type molecules, previously reported by the present authors [Shioya & Takaku (1988). Acta Cryst. A44, 150-157]. A set of pseudo-inverse functions which relate the characteristic values of the intensity distribution to the structural parameters has been proposed, and the structural parameters have been evaluated by iterative calculation of these pseudo-inverse functions and the intensity distribution. It is suggested that the interlayer spacing between carbon layers is distributed according to a skewed function having a longer tail at larger spacings.