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Composite materials (CM) greatly vary in their chemical composition. The content of impurities and doping additives in CM is predetermined.

Properties of epoxy-based composites with various powder and crystalline fillers were studied. Shear characteristics of the compositions were found to be defined by the particle surface morphology of the disperse fillers (DF). The empirical expressions were derived to describe the Young’s modulus (G) and shear strength (τ) of the compositions as a function of the DF concentration and surface roughness (k) of the disperse particles.

1. A technique has been developed for the chemical etching of carbon-graphite materials prepared by thermomechanical treatment. 2. It is shown that, by employing the chemical etching technique, it is possible clearly to reveal the structure in completely smeared microsections obtained by polishing graphitized materials.

The various forms of carbon at present in existence are distinguished from each other by a number of properties, including their relationship to chemical reagents. The so-called amorphous carbon (soot, highly active coals) is easily oxidized by a 30% solution of hydrogen peroxide [10] and adsorbs several dyes (bromothymol blue, etc.) [9], whereas according to our present data graphite remains unaffected by these reagents. In order to conduct a systematic investigation into the chemical properties of various carbon materials and establish their phase relationship, we studied two ways of separating free carbon from refractory compounds: the removal of free carbon by roasting in a muffle furnace at 850°C, and the “wet” oxidation technique.

The authors have developed a technique for producing a rammed carbon packing for metallurgical furnaces. They have determined the optimum component ratio. They show that the best thermal conductivity is that of a packing material based on natural graphite. Compaction of the rammed material improves its properties.