In laser powder bed fusion (L-PBF), a metal powder–based additive manufacturing process, pure titanium powders rely on expensive gas-atomized spherical powders, which poses a significant limitation of material cost. In contrast, non-spherical titanium powders are more cost-effective but their application in L-PBF is restricted their use due to poor flow property and high oxygen content. In this study, a powder mixing strategy with spherical titanium and hydrophobic SiO2 nanoparticle is proposed to improve the flowability and process stability of non-spherical Ti powders. After evaluating flow properties at various mixing ratios, a spherical-to-non-spherical Ti ratio of 4:6 was selected, with SiO2 nanoparticles added during mixing. The uniform distribution of oxide nanoparticles on the powder surfaces was confirmed by SEM and EDS. A maximum relative density of 99.7% was shown by specimens made with L-PBF under various processing parameters. The specimens obtained a tensile strength of 762.6 ± 3.8 MPa and an elongation of 22.1 ± 0.7% at a volumetric energy density of 71.4 J/mm³. This study demonstrates the application of low-cost non-spherical Ti powders in L-PBF is feasible and presents an effective way to simultaneously increase process stability and economic efficiency in titanium additive manufacturing.

This study presents a cost-effective approach to fabricating near β-Ti alloys via in-situ alloying during laser powder bed fusion (L-PBF). A blend of non-spherical pure Ti, 3 wt.% Fe, and 0.1 wt.% SiO2 nanoparticles was used to induce β-phase stabilization and improve flowability. Twenty-five process conditions were evaluated across a volumetric energy density range of 31.75-214.30 J/mm3, achieving a maximum relative density of 99.21% at 89.29 J/mm3. X-ray diffraction analysis revealed that the β-Ti phase was partially retained at room temperature, accompanied by lattice contraction in the α’-Ti structure, indicating successful Fe incorporation. Elemental mapping confirmed that the Fe distribution was homogeneous, without significant segregation. Compared to pure Ti, the Ti-3Fe sample exhibited a 49.2% increase in Vickers hardness and notable improvements in yield and ultimate tensile strengths. These results demonstrate the feasibility of in-situ alloying with low-cost elemental powders to produce high-performance near β-Ti alloys using L-PBF.