STUDYING THE TECHNOLOGICAL POSSIBILITIES OF THE FREE SINTERING METHOD FOR PRODUCING METALLIZED DIAMOND – BOND COMPOSITES

Abstract

The choice of the method of free sintering of metallized diamond-bond composites is justified by energy-saving technology and the absence of expensive molds made of heat- resistant materials and durable graphites used in hot pressing. The possibility of obtaining diamond-metal composites with sufficiently high physical and mechanical properties was achieved by selecting metallic elements of the charge, some of which were plastic, and others were strong and adhesively active to metallized diamond components.

The optimal technological modes for manufacturing a metallized diamond-metal bond composite with the highest physical and mechanical characteristics using the free sintering method have been studied and determined. To increase the wear resistance of the composite, crushed carbide material VK6 was added to the composition of the binder of metal powders Fe, Ni, Cu, Sn.

The grain size of 60...100 microns and the mass content of 10% crushed carbide plates of the BK6 brand in the metal charge were selected in order to increase the hardness, and therefore the wear resistance of the composites without compromising their strength characteristics. Titanium, the metal that is chemically most reactive to it, was chosen as the coating material for diamond powders. Metallization of diamond powders with titanium was carried out by thermal diffusion in a halogen-containing environment according to the method developed at NPUA. This method ensures a strong bond between the titanium film and the diamond grain at low temperatures.

The chemical interaction of all bond elements with each other and with the titanium- metalized diamond grain has been established. The distribution of chemical elements over the surface area of a titanium-metalized diamond - metal bond indicated their chemical bond, which characterizes the strong grain retention of metallized diamonds in the bond. Tests of diamond tools manufactured by free sintering under optimal conditions have shown the feasibility of using this method for the production of certain types of diamond tools.