Keyword: «diamond»

The paper deals with the deposits and extraction of diamonds by seasonal diamond mining enterprises in the Arctic regions of the Sakha Republic (Yakutia). The authors show the increasing role in the region in the extraction of diamonds from alluvial deposits and define the main directions of development of diamond mining in the Arctic regions of the Republic.

The structure and composition of the diamond-matrix interface of a composite diamond-containing material obtained by combining processes of the diamond grains metallization (chromium and iron) and the tungsten-cobalt matrix sintering impregnated with copper have been studied by Raman spectroscopy. It was founded that when diamond is metallized with chromium, there are no graphite-containing formations at the diamond-matrix interface. When diamond is metallized with iron at the interface, graphite is formed as separate isolated areas 1–15 µm in size.

The structure, morphology and composition of the diamond-matrix interface of a composite diamond-containing material obtained by combining processes of the diamond grains metallization (chromium and iron) and the tungsten-cobalt matrix sintering impregnated with copper have been studied by scanning electron microscopy, X-ray microanalysis, X-ray phase analysis and Raman spectroscopy. The specific productivity of diamond dressing tools based on the obtained material has been determined. Diamond metallization with chromium and iron, cause the specific productivity of the tool increase by ~44–62% compared to the same indicator of a tool without diamond metallization.

A complex of methods was used to study the microstructure, elemental and phase composition of a diamond-containing hard-alloy matrix obtained by impregnation of the Fe-C eutectic melt in vacuum. It was found that the matrix consists of phases of tungsten carbide with a relative content of 61.0%, iron carbide – 17.0%, α-Fe – 16.5%, and graphite – 5.5%. The Fe-C eutectic alloy, which acts as a binding component of the matrix, consists of a ferrite-pearlite metal base with graphite inclusions. The microhardness of the matrix based on tungsten carbide impregnated with Fe-C melt is ~11 GPa, which is more than 3 times higher than the microhardness of the tungsten-cobalt matrix obtained by sintering with copper impregnation