L1₂ordering in Ni₃Al-Fe disordered by rapid quenching

Abstract

Abstract Microcrystalline Ni3Al-Fe and Ni3Al alloys with ordered L12(γ') superlattices have been obtained in fully and partially disordered γ states respectively, by very rapid quenching from the melt. Superlattice peaks are absent in the X-ray diffraction patterns of the as-quenched Ni3Al-Fe alloy. The disorder-to-order reaction and L12 superstructure Bragg peaks appear during the post-quench heat treatment. The ratio of the magnitudes of the integrated intensity of the superlattice peaks to that of the fundamental peaks indicate a preference for Fe atoms to occupy Al-type sites in the ordered state.