This article presents the results of studies to determine the influence of the amount of modifiers on the physical and mechanical properties of hard alloy samples based on tungstencobalt carbide. Ultrafine nanopowders of titanium carbide and tungsten carbide were chosen as modifiers. The influence of the amount of modifiers: ultrafine TiC powder from 1 to 6% and WC nanopowder from 1 to 8% on the physical and mechanical properties of hardened alloy samples was studied. Conducted scientific and practical studies show that with an increase in the number of modifiers, the density, hardness and bending strength of the samples increase.