Wear Resistance of High-Entropy Alloys

The tribotechnical properties of high-entropy alloys in pair with 65G steel in air under dry sliding friction conditions are investigated in comparison with wear-resistant steel and powder materials. The sliding friction rate was 6, 8, and 12 m/sec and the pressure was 0.5 and 1.0 MPa. It is determined that the wear intensity of high-entropy alloys at the sliding friction rate 5-10 m/sec under 0.5 and 1.0 MPa loads ranges from 6.1 center dot 10(-10) g/km to 1.6 center dot 10(-9) g/km for the samples and from 5.5 center dot 10(-8) g/km to 1.1 center dot 10(-8) g/km for the counterface. It is established that, when friction, the shear deformations promote the formation of thermally stable nanostructures with grains 30-70 nm in size in the surface layer of the secondary structures. It is shown that the formation of nanostructures is accompanied with 20-30% increase in hardness for both high-entropy alloys and counterface material. It is established that, when friction, high temperatures at the contact points promote the formation of ordered beta-phase with BCC lattice on the friction surface of the Fe25Cr20Ni20 Mn15Co10Al10 high-entropy alloy.