A novel approach for developing Ti6Al4V-Cu alloy with exceptional properties using a developed metallic printer of LPBF

Ti6Al4V has no antimicrobial performance, and copper (Cu) is usually added in Ti6Al4V implants. Nevertheless, brittle Ti₂Cu will be precipitated, greatly affecting the elongation of Ti6Al4V-Cu. To solve these challenges, a novel approach is proposed to prepare Ti6Al4V-Cu alloy using a developed metallic printer of laser powder bed fusion (LPBF). At an optimized laser energy density of 39.51 J/mm³ and 1 wt% Cu, the relative density of Ti6Al4V-Cu is 99.7 %. The ultimate tensile strength and compressive strength of prepared Ti6Al4V-Cu are 1382.35 and 1882.13 MPa, respectively, representing increases of 14.4 % and 36.9 % compared to those of Ti6Al4V. Meantime, the friction coefficient and wear rate are 0.39 and 3.99 × 10⁻⁴ mm³/N∙m, decreasing 46.38 % and 38.29 % correspondingly. Furthermore, electrochemical experiments show that the resistance value of passivated film on Ti6Al4V-Cu is 2.19 × 10⁶ Ω·cm², which is 1.38 times that of Ti6Al4V. Cu atoms were dissolved in Ti6Al4V matrix, leading to the decomposition of the Ti₂Cu phase. The improvement of mechanical, tribological and corrosion resistance properties is attributed to grain refinement, solution strengthening, grain boundary strengthening and decomposition of Ti₂Cu. Our findings provide new insights to prepare Ti6Al4V-Cu with outstanding properties using LPBF, which has bright prospect in aerospace and medical restorations.