Oxidation Behavior of Ni-Based Alloys: Effect of Alloying Additions

Abstract

Ni-based alloys with Al, Fe, Ti, and Nb additions were designed for the molten-glass environment and the oxidation behavior was evaluated by static oxidation in air at 1,050°C for 20 h. The oxidation kinetics results indicate that the increase in iron content from 6 wt% to 20 wt% improved the oxidation rate of Ni-based alloys and promoted the transition from external oxidation to internal oxidation. The introduction of 5 wt% Al into Ni-based alloys retarded such a detrimental effect of iron by the formation of external alumina. The effect of alloying elements on the oxidation process is discussed based on the kinetics and morphology results.