Assessing wear and corrosion in oxide reinforced AlCrFeNi high entropy alloy fabricated via field assisted sintering technique

Abstract

AlCrFeNi high-entropy alloy (HEA) reinforced with 4%wt TiO2 was fabricated through mechanical alloying (MA) followed by Field Assisted Sintering Technique (FAST) at 1100 °C temperature, 50 MPa pressure and 10 mins holding time, with subsequent investigation into FAST-induced powder deformation, microstructure, wear, and corrosion properties. TiO2 slowed down powder deformation during FAST of the AlCrFeNi, reducing density by 0.8%. The microstructure consisted of (Fe, Cr)-enriched BCC and (Al, Ni)-rich B2 phases, with the even distribution of a dark TiO2 phase in the AlCrFeNi HEA. The composite exhibited enhanced properties, including a high indentation resistance of 679 HV. The resistance to corrosion of the AlCrFeNi-TiO2 composite exhibited a substantial enhancement, as evidenced by a significant reduction in the corrosion current density (Icorr). Additionally, the wear tests unveiled improved tribological behavior in the composite, characterized by reduced friction coefficients (CoF) and wear rates. The wear mechanism was abrasive in the alloy and adhesive in the composite.