High temperature oxidation behavior of spark plasma sintered WC-CoCrFeNiAl hard alloys

The oxidation behavior of WC-CoCrFeNiAl hard alloy in air environment under 600–800 °C was studied and compared with that of WC-Co hard alloy. The results showed that the oxidation behavior of WC-CoCrFeNiAl hard alloy was controlled by the chemical reaction at the interface of matrix and oxide layer. The oxidation resistance of WC-CoCrFeNiAl hard alloy was significantly better than that of WC-Co hard alloy, and the high-temperature oxidation gain at 800 °C was only 60% of that of WC-Co hard alloy. The oxidation resistance of WC-CoCrFeNiAl hard alloy increases with the increase of high entropy alloy binder content, and the mass gain of WC-20CoCrFeNiAl hard alloy is only 14% of that of WC-5CoCrFeNiAl hard alloy. The excellent oxidation resistance of CoCrFeNiAl high entropy alloy improving the oxidation resistance of WC-CoCrFeNiAl hard alloys.