Effect of volumetric energy density on the microstructure and electrochemical behavior of selective laser melted Ti6Al4V alloys

Ti6Al4V alloy specimens were prepared by selective laser melting to study the effect of volumetric energy density on its electrochemical behavior. The results show that with the increase of volumetric energy density, the proportion of high-angle grain boundaries and microstructure uniformity of the prepared specimen are enhanced. The prepared specimen has the lowest self-corrosion current density (2.04 x 10-7A/cm2) and impedance with optimum electrochemical corrosion resistance when the volumetric energy density is 90 J/mm3. This is mainly due to the highest proportion of high-angle grain boundaries and uniform microstructure of the specimen, which contribute to the formation of the passivation film. Additionally, the higher (0001) crystal plane texture intensity is also an important factor.