| Abstract Scope |
Mechanical properties, fracture surface and microstructure of Ti6Al4V (Grade 23) tensile rods produced by laser power bed fusion were investigated. Stress-relieved and hot isostatically pressed (HIP) rods were examined for comparison, built both in horizontal (X and Y) and vertical (Z) orientations. The stress-relieved alloy had an average yield strength, tensile strength and elongation of 1158 MPa, 1191 MPa, and 5.9%, respectively, along with more mechanical anisotropy. The HIP rods had an average yield strength, tensile strength and elongation of 946 MPa, 1000 MPa, and 15.5%, respectively. Dimples corresponding to ductile behavior was observed for the HIP rods, and the lack of fusion flaws (i.e., pulled-out powders) were observed in stress-relieved rods. All samples were dense (>99%), but the microstructure, examined by XRD, SEM and TEM, consisted of acicular α’ martensitic needles for stress-relieved rods, while lamellar α + β phases were observed for HIP rods. |