Influence of Processing Parameters on the Microstructure and Properties of Biomedical Ti-15Mo Alloy Fabricated by Laser Selective Melting

To optimize the process parameters for fabricating biomedical Ti-15Mo alloy via selective laser melting (SLM)， this work systematically investigated the effects of laser processing parameters on the relative density， microstructure， mechanical properties， and corrosion resistance of specimens by optical microscopy (OM)， X-ray diffraction (XRD)， scanning electron microscopy (SEM)， universal testing machines and electrochemical workstations.Results showed that with increasing laser energy density， the relative density of Ti-15Mo alloy first progressively increased and then stabilized.The specimens exhibited equiaxed grains along the vertical direction and columnar grains parallel to the deposition direction， with a single β-phase of bcc structure constituting the phase composition.In addition， the mechanical properties of the specimens showed a positive correlation with their relative density.When the laser power was 175 W，the scanning speed was 1 500 mm/s，and the scanning spacing was 80 μm， the relative density of the as-prepared specimen reached 99.84%， and the comprehensive performance was the best.The specimens exhibited the ultimate tensile strength of 801.0 MPa， the elongation of 24.0%and the elastic modulus of 90.6 GPa.Moreover， the specimen demonstrated excellent corrosion resistance with a current density of 0.059 μA/cm2 and corrosion rate of 0.05 μm/a，meeting the stringent requirements for biomedical implant materials.