Effect of Zr, Ti, Ta and Mo addition on high-temperature oxidation and hot corrosion behavior of NiAlY alloys

Abstract

NiAlY alloys with the addition of Zr, Ti, Ta and Mo were prepared by arc melting. The oxidation and NaCl-induced hot corrosion behavior of the alloys were investigated at 650 ℃, with the focus on the effect of element-doping and phase. With the addition of Ti, Ta and Mo, the oxidation resistance of the tested alloys was effectively enhanced compared to the undoped NiAlY alloy. However, the NiZrAlY alloy showed very poor oxidation resistance. Under the NaCl-induced hot corrosion test, the NiTaAlY and NiMoAlY alloys exhibited an improved hot corrosion resistance, while the NiZrAlY and NiTiAlY alloys showed very poor hot corrosion resistance. Moreover, the NiAl and Ni 5 Y phases exhibited different behavior during the oxidation and NaCl-induced hot corrosion tests. • A new type NiXAlY system doped with different alloying elements was designed in this work. • The oxidation and hot corrosion behaviors of NiAlY alloys with different alloying elements addition such as Zr, Ti, Ta and Mo were investigated at 650 ℃. The effects of different alloying elements on oxidation and hot corrosion resistance were investigated. • Y displayed a negative effect in both oxidation and hot corrosion resistance. The degradation mechanisms of Y-rich areas in the oxidation and hot corrosion tests were different.