Damage process in electron-irradiated graphite studied by transmission electron microscopy. I. High-resolution observation of highly graphitized carbon fibre

Abstract Abstract Electron irradiation damage of highly graphitized carbon fibre was examined by means of transmission electron microscopy in a multibeam lattice imaging mode together with selected-area electron diffraction. It was found that the (00.2) lattice spacing was homogeneously increased up to about 11% over the whole irradiated area with increasing irradiation time. The structural order parallel to the basal plane gradually deteriorated, although that perpendicular to the basal planes was comparatively retained. Computer image simulations based on possible model structures so far proposed, in which interstitial atom clusters are incorporated, could not explain the homogeneous dilation of (00.2) lattice fringes. An unconventional idea must be considered for the damage process in graphite.