Titanium and its alloys are well-suited for marine engineering owing to their high specific strength and superior corrosion resistance. However, their high cost remains a key barrier to widespread marine application. Titanium/steel (Ti/Fe) dissimilar materials provide a promising solution by integrating titanium’s corrosion resistance with the high strength of steel, thereby significantly reducing costs. This review systematically assesses the potential preparation strategies for Ti/Fe dissimilar materials, such as explosive welding, rolling, high-energy beam cladding, and cold spray, to meet the large-scale application requirements in marine engineering. Advanced welding techniques for joining Ti/Fe joints are also discussed. The advantages and issues of Ni, Cu, Fe, and Al interlayers suitable for marine engineering applications in inhibiting Fe-Ti IMCs are introduced, with a focus on their potential in promoting the development of economically efficient ocean engineering. A comprehensive evaluation is conducted on the performance of Ti/Fe dissimilar materials, particularly their corrosion resistance and fatigue resistance in marine environments. This review aims to provide a reference for the theoretical research, preparation strategies, and application expansion of low-cost Ti/Fe dissimilar materials in marine engineering.

This study investigated microbiologically influenced corrosion (MIC) and passive-film degradation of a Ti-15Mo-3Al-2.7Nb-0.25Si β titanium alloy exposed to Pseudomonas aeruginosa. The alloy comprised a continuous β-Ti matrix with dispersed α-Ti precipitates, and this α/β dual-phase microstructure provided a potential microstructural basis for spatial variations in passivation behavior among different microregions. During immersion, P. aeruginosa formed a heterogeneous biofilm of bacterial cells and extracellular polymeric substances, altering interfacial mass transfer, oxygen distribution, and local chemistry. Relative to the sterile control, the inoculated group showed increases in maximum pit depth from 2.4 to 4.1 μm and corrosion current density from 8.72 to 17.2 nA cm⁻², while the charge-transfer resistance decreased to 4.32 MΩ cm² after 14 d, confirming enhanced localized corrosion. Mott-Schottky and XPS analyses showed that the donor density increased from 1.07 × 10¹⁹ to 1.29 × 10¹⁹ cm⁻³ and the Ti⁴⁺ fraction decreased from 72.29% to 66.74% and the relative Ti⁰ fraction increased from 7.01% to 17.59%, reflecting increased defect accumulation within the film, impaired passive-film integrity, and reduced local protective capability. P. aeruginosa therefore increases the MIC susceptibility of this β titanium alloy by biofilm-induced interfacial microenvironmental heterogeneity. These findings support MIC assessment and integrated antifouling-anticorrosion surface design for marine β titanium alloys.