The microstructure and microhardness of eleven volumetric cermets based on TiC carbide withnickel- and cobalt-based matrices after liquid-phase sintering at a temperature of 1400℃ were studied. It isproposed to use the research results for the subsequent production of powders for plasma spraying of coatings.The compositions of the matrices and the contents of additional hardening phases and carbon were selectedtaking into account the specific features of the formation of plasma coatings: a decrease in the carbon contentand high solidification rates of the sprayed particles with the formation of additional nanosized carbides andan increase in the volume fraction of carbides from 70 to 88. The traditional composition for cermets withTiC carbide, NiCr–Mo, and industrial powders such as PG-SR2 grade (PN-CrNi80Si2B2) with the composition(wt ) Ni, 13.5 Cr, 2.7 Si, 4.5 Fe, 0.37 C, 1.65 B and TAFA 1241F grade with the composition (wt ) Co,32 Ni, 21 Cr, 8 Al, 0.5 Y were used as the matrix. The ring zone on TiC carbide is formed by sintering withthe participation of WC, Cr_3C_2, TiN, matrix phases, and 1–2.8 wt of additional carbon in the compositionof cermets. As a result, the initial volume fraction of TiC carbide increases from 70 to 88. Additional carbonis also consumed to decrease the oxygen content at the sintering stage (the reduction of oxides). Upon sintering,the cermets have high microhardness values of 1940–3210 kgf/mm~2 at an indentation load of 20 G andlower values at an indentation load of 200 G, which can be explained by the scale factor. The calculated maximumcontribution of the hardness of the hardening phases to the hardness of the cermet was assessed for cermetswith a Co matrix at 3681 kgf/mm~2.
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