Abrasive Wear Resistance of High-Entropy AlCoCuFeNi Alloy in SiC Mixture

The results of tribological tests carried out on two novel high-entropy alloys (HEAs) from the AlCoCuFeNi group are described in this study. Research was carried out using a Miller machine (ASTM G75 standard) in an abrasive slurry environment, which contained SiC and water in a 1:1 ratio. The results obtained showed a higher rate of abrasive wear in the material designated as D3 (total weight loss in D3-1.6g compared to 1.1g in the D5 alloy), characterised by a homogeneous microstructure and hardness of 186 HV5. The second dual phase alloy, designated D5, was characterised by a lower rate of abrasive wear. In this alloy, the appearance of the second phase precipitates, evenly distributed throughout the entire volume, with higher hardness (760 HV0,01) and in a content of approximately 65% has led to a decrease in wear. The different wear resistances of the tested materials are due to differences in the hardness of the phases that constitute the microstructure of the tested alloys and the interaction of hard abrasive particles with the tested material. This has a direct impact on the plastic nature of the deformation in the upper layers of the samples. A characteristic system of linear grooves and protrusions, visible on surface profiles, was observed on the surfaces tested. Small local defects were also observed as a result of hammering and subsequent removal of hard SiC abrasive particles from the alloys tested or, in the case of the D5 alloy, additional removal of precipitates of the harder phase from the matrix.