XRD investigation of the beta-to-omega interface in Ti-15Mo alloy

Some beta-stabilized Ti alloys can form metastable hexagonal omega phase upon quenching or low-temperature annealing. This phase forms ellipsoidal particles whose interface with the parent beta phase is diffuse in nature. The parameters of the interface (e.g., its thickness) are not thoroughly explored yet. Furthermore, there are two perspectives on the omega dimensions – the crystallographic (via diffraction techniques) and the chemical (via atom probe tomography, APT, or small angle X-ray scattering, SAXS). We propose a method of measuring the crystallographic omega dimensions by fitting the estimated peak profile, parametrized by the particle radius and interface thickness, to the experimental peak profiles. The crystallographic insight will be compared to the chemical insight obtained from existing APT data.