부산대학교 도서관

Indentation hardness (H i n ) and strain rate sensitivity (SRS) of additive manufactured Ti–6Al–4V (Ti64) alloys fabricated through both laser powder bed fusion (L-PBF) and electron beam melting (EBM) are investigated. One major difference between these processes is the higher cooling rates associated with the L-PBF. The indentation tests were performed at loading rates of 1, 10, and 50 mN/s. The L-PBF alloy showed a higher hardness value (3.45 GPa at 1 mN/s, 3.57 GPa at 10 mN/s, and 3.66 GPa at 50 mN/s) being correlated with its finer grain structure as compared with the EBM counter material (3.12 GPa at 1 mN/s, 3.37 GPa at 10 mN/s, and 3.55 GPa at 50 mN/s). The indentation SRS was explained based on the print orientation and dislocation density. EBM-Ti64 shows a higher SRS (0.0335 compared with 0.0147 in the L-PBF alloy) due to the rotation of α-prismatic planes along the building direction. • L-PBF and EBM techniques were used to fabricate Ti64 samples • EBSD was employed to study the microstructure of the alloys • The rate-dependent micromechanical properties of the samples were evaluated using nanoindentation • The strain rate sensitivity of the alloys was correlated to the microstructure and texture [ABSTRACT FROM AUTHOR]