Development of α/γ Transformable FeCrAl-ODS Alloys by Nickel Addition

Abstract

Utilizing γ/α transformation allows for a wider range of structure control for Al₂O₃-forming FeCrAl alloys considered as a candidate for the advanced fast reactor fuel cladding. In this research, nickel addition was explored as a method for creating γ-austenite at 1000°C and retaining α-ferrite at room temperature through computing phase diagram by FactSage and implementing HT-XRD & EPMA experiments. In addition, Al₂O₃ scale formation by oxidation test was implemented at 1000°C. Those results indicated that structure control by the γ/α transformation is realized with appropriate aluminum and nickel addition, keeping continuous Al₂O₃ scale formation.

Fig. 1 Pseudo binary phase diagram Fe–12Cr–4.5Al–xNi calculated by FactSage.