FINE-GRAIN GRAPHITE PREPARATION PROCESS Russian patent published in 2005 - IPC

FIELD: nonferrous metallurgy and precision engineering.

SUBSTANCE: invention is intended for use in manufacturing production accessories and tools for electronic treatment. Calcined coke is ground to average particle size between 2 and 20 μm and mixed with medium-temperature coal pitch taken in excess from 3 to 10% of the weight of composition relative to content of pitch providing maximum density and strength of graphite blanks without thermal-vacuum treatment. Resulting mix is subjected to thermal-vacuum treatment under pressure 80-320 hPa and temperature 250-320°C during 1 to 10 h. Thereafter, coke-pitch composition is ground to produce molding powder, from which blanks are pressed. Resulting blanks are fired at 1000-1300°C and graphitized at 2600-3000°C. Fine-grain graphite shows compaction strength 80-120 MPa, density 1.75-1.85 g/cm³, and density variations not exceeding ±0.1 g/cm³.

EFFECT: improved performance characteristics of product.

3 cl, 3 tbl, 22 ex