Solid-particle erosion of a dual-phase AlCoFeNi2 high-entropy alloy

Material removal due to solid-particle erosion results in mechanical failure of equipment and tremendous financial impact. To decrease the removal, materials with a good combination of high hardness and ductility are highly desirable. Dual-phase high-entropy alloys (HEAs) have the potential for impact resistance and have thus attracted attention from researchers. However, there is a lack of knowledge on phase-specific microstructural evolution under repeated particle impacts. In this study, an FCC (face-centred cubic) + B2 dual-phase AlCoFeNi2 HEA was fabricated, and its erosion resistance was tested under a particle velocity range of 97–230 m/s and incident angle range of 20 °-90 ° using nominally 50 μ m angular aluminum oxide particles. 316 stainless steel (SS) was tested under the same conditions as a benchmark. Characterization tools including an electron backscatter diffraction technique were applied to assess the microstructural evolution of the eroded surfaces and subsurface damage. The dual-phase HEA exhibited an approximately 10% lower erosion rate at oblique incidence (