The present work shows the graphene nano powder-assisted micro-electrical discharge process for deposition of high-entropy alloy (HEA) coatings. Results show remarkable improvements in corrosion resistance behavior for MgAz31b workpiece designed for miniaturized system and implant applications. In this work, HEA coatings were prepared at different pulse-on durations and thoroughly examined with respect to their surface morphology, corrosion characteristics, and tribological behavior. Findings reveal that the graphene powder-mixed AlCoCrFeNi HEA coating in electrical discharge processing significantly enhances both corrosion and wear resistance. Among the studied compositions, AlCoCrFeNi exhibited the best performance, achieving a corrosion penetration rate (CPR) of 9.6 mm/year as determined by electrochemical testing. Furthermore, the addition of graphene nano powder during the coating process provided an additional boost to the tribological performance. Graphene enhances plasma channel stability and promotes uniform molten material deposition, resulting in a denser and more defect-free coating compared to conventional electrical discharge machining (EDM) processing.
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