放射光・中性子を用いたα+β型チタン合金の組織解析

抄録

This review described our recent results on the synchrotron X-ray and neutron diffraction-based microstructural characterizations for α + β duplex titanium alloys, with a particular focus on additively manufactured (AM) Ti−6Al−4V alloys. The use of synchrotron radiation enables dislocation structure analysis, which utilizes convolutional multiple whole profile (CMWP) fitting, not only for the α-matrix but also for the fine β-phase in the acicular microstructures via line profile analysis. Moreover, we employed Rietveld texture analysis and successfully determine the textural evolution upon multiple phase transformations during electron beam powder bed fusion. These techniques revealed novel understandings on the phase transformation and resulting microstructural evolution in AM processes and can be applied for other duplex titanium alloys as well as plastic deformation analysis based on in-situ measurements upon external loading. The advantages and limitations of the employed techniques are also discussed.