Co- and Fe-based alloys produced by powder technology are being widely used as a matrix for diamond-containing composites in cutting, drilling, grinding pplications, etc. The severe service conditions demand that the mechanical and tribological properties of these alloys be improved. Development of metal-matrix composites (MMCs) and alloys reinforced with nanoparticles is a promising way to resolve this problem. In this work, we have investigated the effect of nano-sized WC, ZrO₂, Al₂O₃, and Si₃N₄ additives on the properties of sintered dispersion-strengthened Co- and Fe-based MMCs. The results show an increase in the hardness (up to 10 HRB), bending strength (up to 50%), wear resistance (by a factor of 2–10) and a decrease in the friction coefficient (up to 4-fold) of the dispersion-strengthened materials. The use of designed alloys as a binder of cutting diamond tools gave a 4-fold increment in the service life, without reduction in their cutting speed.

The effect of added Mo, WC, and ZrO2 nanopowders on the graphitization of diamond grains in metal–matrix composites was studied by Raman spectroscopy. In the presence of Mo and ZrO2 nanoadditives, the graphitization process was found to get intensified. But the addition of WC nanopowder was found to suppress the graphitization by 25–30%. This can be expected to improve the adhesion of binder to diamond grains and hence the service life of related cutting tools