Use of Titanium Plate & Sheets in Aircraft: Properties and Benefits

Titanium plates and sheets are critical structural materials in modern commercial and military aviation. The aerospace industry uses titanium because it combines low density with high tensile strength, exceptional corrosion resistance, and the ability to withstand extreme heat — all properties that aluminium and steel cannot deliver simultaneously. Titanium accounts for approximately 15 percent of the Boeing 787 Dreamliner‘s empty weight, a figure that reflects how deeply the material is woven into next-generation aircraft design. The Airbus A350 XWB incorporates roughly 14 percent titanium by total airframe weight, used across landing gear, frames, and structural attachments.

The metal first entered aerospace use in the 1950s, when the emerging jet age demanded materials that aluminium could not provide at high operating temperatures. The titanium industry was established primarily in response to the aerospace sector, which used it in airframe structural components, hydraulic systems, engine parts, rockets, and missiles. Since then, every generation of commercial aircraft has increased its titanium content, and the Boeing 787 and Airbus A350 represent the peak of that trend. Twin-aisle aircraft use a significantly higher percentage of titanium than single-aisle types, and next-generation designs are expected to continue that trajectory.

What Is Titanium, And Why Does Aviation Use It?

Titanium is the fourth most abundant structural metal in the Earth’s crust, ranking behind aluminium, iron, and magnesium. It was first discovered in 1791 by British mineralogist William Gregor. Pure titanium was not produced until 1910, when American metallurgist Matthew A. Hunter reduced titanium tetrachloride with sodium. Its high extraction and refining costs limited commercial use until World War II revealed its value to the military.

In aviation, the fundamental driver for titanium adoption is weight reduction. A lighter aircraft consumes less fuel, achieves higher payload capacity, reduces operational costs, and lowers environmental impact. Titanium’s density is about 60 percent that of steel, yet its tensile strength matches or surpasses many steel alloys. Titanium plates are stronger than steel but approximately 45 percent lighter. That combination makes it the preferred choice wherever structural integrity and weight savings must coexist.

Key Physical Properties of Titanium Plates and Sheets

The properties that make titanium plates indispensable to aviation engineers are well-documented and measurable. They are:

• High strength-to-weight ratio: Titanium is stronger than steel but significantly lighter, enabling designers to reduce structural weight without sacrificing load-bearing capacity.
• Corrosion resistance: Titanium naturally forms a stable, self-healing oxide film that protects it against oxidation and corrosion from moisture, fuels, and chemicals.
• Thermal stability: Titanium alloys can operate for extended periods at temperatures between 450°C and 500°C, making them suitable for high-temperature zones in aircraft engines.
• Thermal expansion compatibility with composites: Titanium shares similar thermal expansion rates with carbon fibre-reinforced polymer (CFRP), which makes it the preferred interface material where composite panels meet metallic structures.
• Non-magnetic: This makes titanium plates suitable for use near sensitive avionics and navigation equipment.
• Biocompatibility: While primarily relevant to medical use, this property confirms titanium’s chemical inertness — an advantage in aircraft environments where contact with hydraulic fluids and fuels is constant.

Titanium also maintains its structural integrity at supersonic speeds, where aerodynamic heating would warp or degrade other materials. This is why titanium featured in the construction of Concorde, one of the most demanding airframes ever built.

Titanium Grades Used in Aviation

Not all titanium is identical. The aerospace industry uses specific grades depending on the application and performance requirement.

Grade 2 (Commercially Pure): Grade 2 is an unalloyed, medium-strength product used in airframes, aircraft engines, and marine parts, valued for its excellent weldability and corrosion resistance. It is the most widely used commercially pure grade in the aerospace sector.

Grade 4 (Commercially Pure, Highest Strength): Grade 4 is the highest-strength pure titanium and is used almost exclusively in airframe and aircraft engine parts, as well as hydraulic tubing. Its formability and corrosion resistance make it a reliable choice for structural components exposed to cyclic stress.

Grade 5 — Ti-6Al-4V (Aircraft Grade): This is the workhorse of aerospace titanium. Ti-6Al-4V accounts for over 50 percent of the total titanium-based materials market. The alloy combines 90 percent titanium with 6 percent aluminium and 4 percent vanadium. It is used to produce aircraft engine components, aircraft structural components, and fasteners, offering an advantageous combination of light weight, corrosion resistance, and high strength at low to moderate temperatures. Engineers refer to it as “aircraft grade” titanium, and it is certified under aerospace standards AMS 4911, AMS 4928, and MIL-T-9046.

Near-Beta Alloys (Landing Gear): For the most heavily loaded structures, near-beta titanium alloys are specified. These alloys achieve tensile yield strengths of 170–180 ksi and ultimate tensile strengths of 180–195 ksi, providing the fracture toughness and fatigue resistance that landing gear demands during thousands of cycles of touchdown loads.

Where Titanium Plates and Sheets Are Used in Aircraft

Titanium appears throughout the aircraft, from the airframe skin to the deepest recesses of the jet engine. Its applications fall into several distinct categories.

Airframe Structures

Titanium plates are used in fuselage frames, wing structures, and fasteners, improving aircraft durability and fuel efficiency. Wing box fittings — the large structural elements that join the wings to the fuselage — are a particularly demanding application. Boeing’s own chief project engineer on the 787 programme explained that titanium was chosen for the large fittings joining the 787’s wings to its fuselage because “it’s very light and it does very well in a highly loaded situation”.

Bulkheads, floor beams, and pressure frame rings in wide-body aircraft are also commonly produced from titanium sheet and plate. Titanium alloys are used in aircraft beams and bulkheads where weight reduction and structural strength must coexist. In our previous reports, we have documented how the Boeing 787’s composite-heavy construction achieves a 25 percent reduction in fuel use versus the aircraft it replaces, and titanium structural components play a direct role in enabling that efficiency.

Jet Engine Components

Titanium is indispensable in jet engines because of its heat resistance and fatigue strength. It is used in forged titanium fans, compressor discs and blades, engine cowlings, and exhaust systems. Fan blades and compressor discs rotate at extreme speeds under intense thermal loads — conditions that rule out aluminium entirely. Titanium alloys operate efficiently at temperatures between 450°C and 500°C for extended periods, enabling sustained use in compressor stages where temperature and pressure increase with each successive stage.

Landing Gear

Landing gear must absorb enormous impact loads repeatedly and reliably across decades of service. Near-beta titanium alloys engineered for landing gear deliver elongation values of 10–15 percent and reduction-of-area measurements of 25–35 percent, ensuring adequate ductility for damage tolerance. This combination of high strength and fracture toughness prevents catastrophic failure under the dynamic shock of touchdown.

Fasteners

Tens of thousands of fasteners hold a modern airliner together. Ti-6Al-4V fasteners achieve a double shear strength of 103 ksi (710 MPa), enabling the replacement of heavier iron-based fasteners in weight-critical assemblies. The mass savings from fastener substitution alone, across an aircraft with hundreds of thousands of fastening points, contribute meaningfully to overall empty weight.

Heat Exchangers and Hydraulic Systems

Titanium’s high thermal conductivity allows it to efficiently transfer heat away from critical parts in aviation cooling systems. Hydraulic system tubing made from Grade 4 titanium combines pressure resistance with corrosion immunity — important in an environment where hydraulic fluid and fuel exposure is constant.

Titanium’s Compatibility with Composite Materials

A less-discussed but strategically important property of titanium is its compatibility with carbon fibre composites. Modern wide-body aircraft like the 787 and A350 use CFRP for their fuselage barrels, wing skins, and major structural panels. Aluminium and CFRP are galvanically incompatible — aluminium corrodes rapidly when in direct contact with carbon fibre. Titanium does not share this vulnerability.

By sharing the same thermal expansion rates as many popular composite materials, titanium is highly favoured as a composite interface material. This compatibility reduces thermal stress at join points between composite panels and metal structure during the extreme temperature swings of high-altitude flight. It is a key reason why the rise of composite design is a strong indicator of additional increases in titanium production. The Boeing 787 is approximately 50 percent composites by weight, and the direct pairing of CFRP with titanium frames and fittings is essential to that architecture.

Titanium in the Boeing 787 and Airbus A350

The Boeing 787 Dreamliner and Airbus A350 XWB are the clearest evidence of how seriously the industry has committed to titanium. The 787 is 50 percent composites by weight, 20 percent aluminium, 15 percent titanium, 10 percent steel, and 5 percent other materials. The A350 consists of 52 percent fibre composites, 20 percent aluminium alloys, 14 percent titanium, 7 percent steel, and 7 percent other materials. Both programmes reflect a deliberate shift away from aluminium-dominated construction toward a titanium-composite hybrid architecture.

The 787 in particular increased titanium content compared to earlier Boeing models. The rise in composite usage on the 787 directly corresponded with increased titanium use — to approximately 14–15 percent of the total airframe — because titanium is uniquely positioned as a composite interface material. Twin-aisle aircraft use a higher percentage of titanium in their airframes, engines, and parts than single-aisle planes, and the 787 and A350 mark the high point of that engineering philosophy in production aircraft today.

Aviospace has previously examined in detail how the 787’s material choices drive its 25 percent fuel efficiency advantage over the aircraft it replaces, and titanium’s weight savings in structural applications are a direct contributor to that performance.

 Strategic Vulnerabilities in the Titanium Chain Supply

The aerospace industry’s dependence on titanium has a geopolitical dimension. For decades, Russia’s VSMPO-AVISMA — the world’s largest producer of aerospace-grade titanium — supplied the majority of Boeing and Airbus’s needs. Before Russia’s 2022 invasion of Ukraine, VSMPO was believed to supply roughly 80 percent of Boeing’s titanium and approximately 60 percent of Airbus’s. This created a significant concentration risk in both companies’ supply chains.

Boeing halted all direct titanium imports from Russia in March 2022. Airbus was slower to act; its CEO Guillaume Faury stated in June 2022 that “imposing sanctions on titanium from Russia would mean imposing sanctions on ourselves”. Despite that position, Airbus has since reduced its Russian sourcing significantly. Airbus has diversified supply and is now estimated to source approximately 20 percent from Russia, with further reductions anticipated.

The crisis accelerated investment in alternative sources. France’s Aubert & Duval modernised its 60,000-tonne press to produce large forgings, while in the United States, ATI Titanium, TIMET, and Howmet Aerospace expanded melt and forge capacity and invested in recycling infrastructure. Japan also holds significant capacity, with Osaka Titanium, Toho Titanium, and ATTM combining for roughly twice the sponge production capacity of VSMPO. The structural shift in titanium sourcing is ongoing, and aviation manufacturers are actively building more resilient supply chains that do not depend on any single nation.

Benefits of Titanium Plates and Sheets in Aviation

The commercial case for titanium in aircraft construction rests on several concrete and measurable benefits:

• Weight reduction: Titanium delivers steel-equivalent strength at roughly 60 percent of steel’s density, directly reducing airframe mass and improving fuel efficiency.
• Longevity and low maintenance: Titanium can withstand severe environments, which lowers replacement and maintenance expenses over time. Its corrosion immunity eliminates the need for protective coatings that aluminium requires.
• Temperature performance: Titanium retains structural integrity at temperatures that would weaken aluminium, making it irreplaceable in engine-adjacent zones.
• Composite compatibility: Titanium’s thermal expansion match with CFRP and its galvanic neutrality make it the only practical metallic partner for composite structures in primary airframes.
• Fatigue resistance: Titanium components withstand the tens of thousands of pressurisation cycles and landing loads that define an aircraft’s service life.
• Fabrication flexibility: With appropriate tooling and welding in inert atmospheres, titanium sheets can be fabricated into complex, precise aerospace components. Ti-6Al-4V is also suitable for additive manufacturing, enabling near-net-shape production of complex parts.

The aerospace sector’s adoption of titanium is not a trend — it is a structural reality embedded in every commercial widebody aircraft flying today and in every next-generation programme in development.