Mechanical activated synthesis of alumina dispersed FeNiCoCrAlMn high entropy alloy

The present research aims to investigate the effect of oxide dispersion on the synthesis of High-Entropy (HE) alloy and its properties. For this FeNiCoCrAlMn High-Entropy (HE) alloy dispersed with 2 wt percentage alumina (Al2O3) was synthesized by mechanical activated synthesis. The mechanical activation was carried out by milling the elemental powder mixture of aluminum, cobalt, chromium, iron, nickel and manganese in an equiatomic ratio up to 20 h 2 wt% of Al2O3 was added during mechanical alloying to obtain oxide dispersed HE alloy. Upon pyrolysis at high temperature FCC emerged as major phase in both alloys (with and without oxide dispersion). The alumina dispersed HE alloy shows increase in size of AlNi and CrFeMn rich phase after sintering, relatively less thermal expansion coefficient and better oxidation resistance than HE alloy without oxide dispersion. Hardness was found to be doubled after adding 2% alumina. The obtained result indicate that oxide dispersed HE alloy can be useful material for high temperature coating application. (C) 2016 Elsevier B.V. All rights reserved.