Superior corrosion-resistant cold sprayed titanium coatings with fully dense microstructure after electron beam modification

In this study, electron beam modification (EBM) technology was employed to enhance the surface properties of cold-sprayed (CS) titanium (Ti) coatings without inducing oxidation or compromising adhesion strength. The influence of EBM on corrosion behavior was investigated by analyzing porosity reduction and microstructural evolution. EBM effectively eliminates defects inherent to the CS process, and significantly reduces porosity from 11.5 % to < 0.5 % by adjusting the energy input between 29 ∼ 62 J mm⁻³. The resulting melted layer consists of fine lamellar α Ti grains with dispersed needle-like α’ Ti phases (1.6 ± 0.5 μm). Electrochemical analysis demonstrates that EBM-processed CS Ti coatings maintain impermeability even after 24 h immersion in 10 wt% HCl solution, confirming enhanced corrosion protection performance. Furthermore, the EBM melted layer (energy input: 45 J mm⁻³) exhibits a lower corrosion current density (0.8 μA cm⁻²) and higher charge transfer resistance (2190 Ω cm²) compared to bulk TA1 (1.2 μA cm⁻², 513 Ω cm²), indicating superior corrosion resistance. These results validate EBM as an effective method for enhancing the surface integrity and corrosion protection performance of CS Ti coatings. This study presents a novel, environmentally friendly, and cost-effective approach for fabricating high-quality, corrosion-resistant CS Ti coatings.