| Summary: | Evaporated carbon has been used for graphitization studies in the heat treatment range 1000 — 2400°C, using the techniques of electron diffraction and electron microscopy for characterisation. It has been established that the material is graphitizing, and the results indicate that even for relatively low heat treatment temperatures, (1000°C — 1640°C), there exist at least two stages in the crystal growth process. A value of approximately 2 eV, (46 kcal/ mole), has been obtained for the activation energy corresponding to the first of these stages. The causes of the scatter in results have been investigated, but it is indicated that the elimination of these effects requires more sophisticated equipment than that used in the present study. The nature of the scatter, together with results from the electron microscopy studies suggest that the techniques used may be more revealing than the more common X—ray technique in graphitization studies. The discovery that anisotropic layer plane growth may sometimes occur is an illustration of this point. The detection of the influence of specimen composition or heat treatment atmosphere was hampered by the presence of the large scatter in the data, and no positive result was found, although a catalytic action of iron seems probable. Electron microscopy of specimens heat treated at the higher temperatures, (1640°C - 2400°C), has allowed the identification of crystallite boundaries, both in bright field and dark field conditions. The orientation of the crystallites revealed by moire patterns in the dark field image obtained from the basal plane reflection, relative to the local film direction, has been established, and shown to coincide with the expected condition of preferred orientation.
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