Three broad types of natural graphites are recognized: flake, vein, and amorphous. The compaction of graphite powders, representing these types, into coherent binderless artifacts at room temperature and pressures up to 125, 000 psi has been studied. The graphite powders were characterized as to their particle size distributions, crystallinity, relative crystallite alignment, surface areas, and surface homogeneities. The compacts were characterized as to their surface area, density, pore size distributions, and compressive strengths. It is concluded that chemical bonding between atoms on a small fraction of adjacent particle surfaces is of primary importance in determining compact strength, with van der Waals attractive forces between basal plane surfaces also playing a role.

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A simple method of analysis is described to determine the true crystallite thickness and the range of fluctuation of the layer spacing in graphitic carbon from results of x-ray diffraction line breadth measurement. This is not a new technique, but its remarkable usefulness in the field of carbon research has not been known widely. By plotting the reciprocal of the crystallite thickness L_c (00l) against the order of diffraction, one can obtain the true crystallite thickness by extrapolation of the curve and the lattice strain from its slope. For pyrolytic graphite it is shown that the true crystallite thickness is very large, being more than several thousand angstroms, even in as-deposited state, though the apparent L_c (002) is much smaller. Graphitization eliminates the strain, thus increasing the apparent crystallite thickness. A tentative equation correlating L_c (002) and the observed layer spacing in graphitic carbons is proposed.

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It has been found that the carbon products are prepared from the variant pitch material alone without any binding material and any filler. The standard procedure of the new method and some properties of the products are described in this report.
The variant pitch materials are prepared from coal -tar pitch and otherpitch -like materials by use of the varied pretreatments, for example, distillation, ozonization, oxidation in air or chlorination. The higher softening points than 170°C are required to the variant pitch materials available for this method. Specimens are formed by pressing (100-2000Kg/cm²) or slipcasting .After preheatingin air, carbonization is carried out under nitrogen up to the desirable temperature.
The properties of the products obtained vary in the following ranges with the sort of the variant pitch and the condition of moulding.
Shore hardness 60-130, porosity 60-8%, bulk density 0.75-1.40.

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