1.Exceptional Strength-to-Weight Ratio (High Strength, Low Density): Titanium has a density of about 4.5 g/cm³, which is only 60% that of steel, yet its strength is comparable to many high-strength steels. This means that for the same strength and stiffness requirements, using titanium alloys can significantly reduce weight compared to steel. Weight reduction is a perpetual theme in aerospace; every kilogram saved translates to substantial fuel efficiency, longer range, or greater payload capacity.
2.Excellent Corrosion Resistance: A dense, stable oxide layer (TiO₂) forms on the surface of titanium, giving it极高的 resistance to atmosphere, seawater, and chemicals common in aerospace (like hydraulic fluid and de-icing fluid). Its corrosion resistance is far superior to stainless steel. This greatly enhances component lifespan and reliability while reducing maintenance costs.
3.Good High-Temperature Performance: Conventional titanium alloys (like Ti-6Al-4V) can operate stably long-term at 400-500°C, while some specialized high-temperature titanium alloys (like Ti-Al intermetallic compounds) can withstand temperatures up to 600°C and above. This makes it ideal for hot-section components of aircraft engines.
4.Compatibility with Composite Materials: Titanium has an electrochemical corrosion potential similar to Carbon Fiber Reinforced Polymer (CFRP) composites. When the two are in contact, they do not suffer from severe galvanic corrosion. Therefore, titanium is often used for fasteners, brackets, and junctions connected to composite components.
The engine is the "heart" of an aircraft and the component with the highest usage of titanium alloys (accounting for about 25%-40% of the engine's total weight).
Fan Blades: The front fan blades of modern high-thrust turbofan engines (like the LEAP, GEnx) commonly use titanium alloys. They require extremely high strength to withstand enormous centrifugal forces and potential foreign object impacts.
Compressor Discs and Blades: Discs, blades, and casings in the low-pressure stages of the compressor extensively use titanium alloys. These components operate in high-temperature, high-pressure environments, demanding materials with high strength, fatigue resistance, and creep resistance.
Engine Nacelles and Struts: These structural components also use significant amounts of titanium alloy for weight reduction.
In the aircraft airframe, titanium alloys are used for critical load-bearing structures, particularly in areas where traditional aluminum alloys cannot meet requirements.
Landing Gear Components: The landing gear must withstand the immense impact forces during landing and static loads, making it one of the highest-load components on an aircraft. High-strength titanium alloys (like Ti-10V-2Fe-3Al) are used to manufacture critical landing gear beams, struts, and torque links.
Wing and Fuselage Junctions: Critical load-bearing components like the center wing box connecting the wings to the fuselage, flap tracks, and keel beams often use high-strength titanium alloy forgings due to concentrated loads.
Fasteners: Titanium alloy rivets, bolts, screws, and other fasteners are widely used because they are strong, lightweight, and corrosion-resistant.
Hydraulic Systems and Pipelines: Due to titanium's excellent corrosion resistance, it is often used to manufacture complex hydraulic pipeline systems, ensuring long-term reliability.
In the space sector, the benefits of weight reduction are even more significant (directly related to launch capacity), alongside the need to withstand extreme temperature environments and the vacuum of space.
Rocket Engines: Components of liquid-fueled rocket engines like propellant tanks, turbopumps, and injectors use titanium alloys to withstand the corrosion of cryogenic liquid oxygen/hydrogen and high pressures.
Pressure Vessels: Titanium alloy gas cylinders used for storing high-pressure gases (like helium) and propellants are lightweight, have high pressure resistance, and offer good reliability.
Satellite Structures: Satellite brackets, connection frames, camera mirror barrels, and other structural components use titanium alloys to meet stringent requirements for structural stability, lightweight design, and high stiffness in the space environment.
Manned Spacecraft: Crewed spacecraft like the Shenzhou and Soyuz use titanium alloys extensively in the load-bearing structures of their return modules.
