Abstract:With the deepening advancement of the China''s Maritime Power Strategy, the titanium alloys, due to their low density, high specific strength and excellent corrosion resistance, have demonstrated excellent weight reduction and corrosion resistance effects in the pressure-resistant shells of deep-sea submersible vessels and seawater pipeline systems, extending the service life of equipment, reducing maintenance costs and overall usage costs, and showing significant application value in the fields of ships and Marine engineering. The paper first elaborates on the core requirements of naval ships and marine engineering for titanium alloys, including large-scale components, high strength and toughness, corrosion resistance, and long-term service performance. Subsequently, focusing on different service environments such as deep-sea submersible pressure hulls, seawater piping systems, and power systems, systematic review is provided on the composition, microstructure, properties, and engineering applications of typical titanium alloys like Ti80 and TC4. Furthermore, emphasis is placed on discussing the current research status of long-term mechanical properties of titanium alloys in deep-sea environments, such as stress corrosion behavior, creep, and fatigue. At present, long-term performance data of titanium alloys in real marine environments are still insufficient, and a unified evaluation system and standard has not yet been established. The paper also highlights the existing shortcomings and technical challenges hindering the large-scale application of titanium alloys in the marine sector, including high manufacturing costs and insufficient material experimental data under deep-sea environments, and the further systematic research is still required to support the high-quality development of China''s marine equipment.