| Summary: | This study investigates the influence of 3 vol.% Al<sub>2</sub>O<sub>3</sub>, 3 vol.% TiO<sub>2</sub>, and 3 vol.% Y<sub>2</sub>O<sub>3</sub> in the CrFeCuMnNi equimolar high-entropy alloy on its microstructural changes and corrosion resistance. These oxide-dispersed high-entropy composites (ODS-HECs) were synthesized via high-energy ball milling (50 h) followed by uniaxial hot-compaction (550 MPa, 45 min), medium-frequency sintering (1100 °C, 20 min), and hot forging (50 MPa). The microstructures of the developed composites produced a stable FCC phase, a small amount of ordered BCC-B2 structure, Fe<sub>2</sub>O<sub>3</sub>, and corresponding dispersed oxide phases. The corrosion of the developed high-entropy composites was tested in 3.5% NaCl solution using several electrochemical techniques. The results revealed that the corrosion rate (R<sub>Corr</sub>) decreased with the incorporation of oxide particles. Among the investigated samples and based on the electrochemical impedance spectroscopy results, CrFeCuMnNi-3 vol.% TiO<sub>2</sub> ODS-HECs were seen to possess the highest value of corrosion resistance (R<sub>P</sub>). The change in the chronoamperometric current with time indicated that the CrFeCuMnNi alloy suffered pitting corrosion which decreased when Al<sub>2</sub>O<sub>3</sub> was added, forming a CrFeCuMnNi-3 vol.% Al<sub>2</sub>O<sub>3</sub> sample. In contrast, the incorporation of a 3 vol.% Y<sub>2</sub>O<sub>3</sub>, and 3 vol. TiO<sub>2</sub>, prevents pitting.
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