Microstructure evolution and corrosion performance of LPBF-fabricated Ti-6Al-4V with nano-Mo reinforcement

This study systematically investigates the effects of nano-Mo addition and linear energy density on the microstructure-property relationships of Ti-6Al-4V fabricated by laser powder bed fusion (LPBF). Experimental characterization and electrochemical analysis reveal that 7 wt. % nano-Mo incorporation combined with optimized linear energy density (0.21 J/mm) simultaneously enhances mechanical strength and corrosion resistance. Microstructural analysis reveals that the addition of nano-Mo reduces the grain size by 50.4% (from 141 to 70 nm), while maintaining a homogeneous distribution of the microstructure, resulting in a peak microhardness of 413.5 HV0.2. Electrochemical measurements show that the optimal specimen achieves exceptional corrosion resistance with charge transfer resistance (3.407 × 104 Ω cm2) increasing by 78.4% compared to unmodified Ti-6Al-4V. This study provides foundational insights into the development of high-performance titanium nanocomposites fabricated via LPBF, particularly for biomedical applications requiring combined strength and long-term durability.