2025/08/22 by Dhekne, Pushkar Prakash, Prabhu, Nikhil, Bönisch, Matthias +3
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2508.16367
Despite the significant application potential of laser powder bed fusion (L-PBF) processed Ti-6Al-4V components, a detailed understanding of their deformation mechanisms remains limited. This study investigates the deformation behavior of the α^′ and α phases in the as-built and heat-treated specimens, respectively, using in-situ high-energy X-ray diffraction (HEXRD) combined with crystal plasticity modeling. Both phases exhibited similar elastic anisotropy, with the highest modulus along \00.2\ and the lowest along \10.0\, although the α phase consistently showed higher directional moduli than the α^′ phase. Their plastic deformation responses differed markedly: in the as-built α^′ phase, slip activation followed the sequence prismatic → basal → pyramidal I ⟨ c+a ⟩, whereas in the heat-treated α phase, the sequence was basal → prismatic → pyramidal I ⟨ c+a ⟩. Analyses of full width at half maximum (FWHM) and diffraction peak intensities further supported these observations. Finally, inverse modeling within a crystal plasticity framework was employed to determine slip family--specific critical resolved shear stresses (CRSS), revealing higher CRSS values in the α^′ phase for all slip systems except the prismatic family.