In situ high-energy synchrotron X-ray diffraction reveals the role of texture on the activation of slip and twinning during deformation of laser powder bed fusion Ti-6Al-4V

The deformation behavior of Ti-6Al-4V processed by laser powder bed fusion (LPBF) is investigated by in situ high-energy synchrotron X-ray diffraction (HEXRD) during uniaxial compression. The initial microstructure of the alloy consists of a fine lamellar α + β microstructure where α lamellae are separated by thin continuous β layers within prior β grains. The anisotropy of the alloy is studied in the deformation direction using samples that are built at the angles of 0°, 45°, and 90° with respect to the LPBF base plate. The sample oriented at 0° presents higher strength–ductility trade-off compared with the conditions oriented at 45° and 90°. The in situ HEXRD experiments continuously reveal the microstructure response during deformation and that the textures for each orientation are associated with a different activation sequence of deformation mechanisms. (© 2021 Wiley-VCH GmbH)