WC‐(Fe‐Mn‐C) composites with γ‐iron and γ + α’ matrices were sintered and then tested at sliding speeds in the range 7–37 m/s. The coefficient of friction was exponentially reduced as a function of sliding speed reaching its minimum at 37 m/s. This behavior was provided by the mechanochemical formation of iron tungstate FeWO4 on the worn surfaces of composite samples. The lubricating effect of iron tungstate did not, however, allow for a reduction in wear. The worn surface was represented by a 3–10 μm‐thickness tribological layer composed of fine WC and iron particles cemented by FeWO4. This layer provided the self‐lubricating effect in high‐speed (high‐temperature) sliding because of its easy shear and quasi‐viscous behavior. The underlying 25–65 μm of thickness layer was composed of only heat‐affected WC and recrystallized iron grains.
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