2024年8月13日、東レ・コンポジット・マテリアルズ・アメリカ社は、米国アラバマ州ディケーター工場でTorayca T1100炭素繊維生産ラインが稼働したと発表しました。この生産ラインは、米陸軍の将来長距離強襲航空機（FLRAA）プロジェクトの主要部品の研究、開発、製造を全面的にサポートします。FLRAAは、東レのT1100炭素繊維を決定的に選択した最初の公に報告された軍用航空プロジェクトにもなりました。

技術の継続的な進歩により、新素材の開発と応用は防衛産業においてますます重要な役割を果たしています。優れた性能を持つ炭素繊維複合材は、軍事分野で最も注目される素材の 1 つとなっています。炭素繊維複合材は、高強度、高弾性率、低密度、耐腐食性、耐疲労性を備えており、軍事装備の性能向上、コスト削減、戦闘効果の向上に欠かせないものとなっています。

この記事では、陸上防衛分野における炭素繊維複合材の主な用途について詳しく紹介します。

パート1:

炭素繊維複合材料の特性と用途

高強度、高弾性
炭素繊維複合材は、鋼鉄やアルミニウムなどの従来の金属材料をはるかに上回る強度と弾性率を有しており、構造強度を確保しながら装備品の大幅な軽量化を実現します。例えば、米国のF-22戦闘機では、重要な構造部分に炭素繊維複合材を使用しており、機体の強度を維持しながら機体全体の重量を効果的に軽減し、飛行性能と操縦性を向上させています。

低密度

炭素繊維複合材の密度は、鋼鉄の約 4 分の 1、アルミニウムの約半分です。このため、特に高い機動性と長距離運用能力を必要とする兵器や装備では、軽量化に大きな利点があります。たとえば、欧州の A400M 軍用輸送機では、機体構造に炭素繊維複合材を多用しており、従来の金属構造に比べて機体の重量が大幅に軽減され、積載量と航続距離が向上しています。

耐腐食性

炭素繊維複合材は耐腐食性に優れているため、過酷な環境でも長期間使用できます。これは、海洋や砂漠などの環境で頻繁に運用される軍事機器にとって特に重要です。たとえば、米国海軍の艦艇の一部では、重要な領域に炭素繊維複合材を使用しており、海水による腐食に効果的に抵抗し、メンテナンスコストを削減しています。

疲労耐性

Carbon fiber composites exhibit excellent fatigue resistance, meaning they can withstand long-term cyclic loading without experiencing fatigue failure. This is crucial for aircraft that require frequent takeoffs and landings, high-speed flights, and for ships that endure prolonged maritime operations. For example, the Boeing 787 commercial aircraft extensively uses carbon fiber composites, demonstrating outstanding fatigue resistance in long-term commercial service. This experience has also provided valuable insights for the design and application of military aircraft.

Part 2:

Application of Carbon Fiber Composites in Military Aircraft

Reducing Weight to Improve Performance
For military aircraft, reducing weight is key to enhancing performance.  In supersonic aircraft, such as the J-20 and F-35, reducing weight by just 1 kilogram can not only bring economic benefits of several thousand dollars but also improve the aircraft's maneuverability, giving it a significant advantage on the battlefield. By using carbon fiber composites, the weight of the J-20's airframe is reduced by approximately 9% compared to using aluminum alloy materials. This weight reduction greatly contributes to improving the aircraft's maneuverability and endurance. The U.S. F-35 fighter jet uses about 35% carbon fiber composites, effectively reducing the airframe's weight, improving fuel efficiency, and increasing its combat radius.

Increasing Structural Strength
The structural strength of carbon fiber is very high, allowing the aircraft's airframe to be both lightweight and robust. Advanced large aircraft and fighter jets can extensively use carbon fiber composites. For example, the Eurofighter Typhoon's airframe surface is already composed of 70% carbon fiber composites. In practical applications, carbon fiber composites can withstand the aerodynamic forces and maneuvering loads during high-speed flight, ensuring the structural safety of the aircraft.

Reducing Maintenance Costs
Fighter jets often operate in coastal areas where the air contains high levels of salt, which can easily corrode traditional metal materials, leading to high maintenance costs. However, carbon fiber composites have strong corrosion resistance and are unaffected by the salt content in the air, making the aircraft less prone to corrosion and thus reducing maintenance expenses. For instance, France's Rafale fighter jet uses carbon fiber composites in areas that are particularly susceptible to corrosion, which has reduced the frequency and cost of maintenance.

Stealth Capabilities
Through carbon fiber modification or the addition of special substances, carbon fiber composites can also enhance stealth capabilities. Specially treated carbon fiber composites can absorb radar waves, reducing radar wave reflection and thus decreasing the likelihood of detection by radar. Russia's Su-57 fighter jet uses stealth-capable carbon fiber composites in some parts of its airframe, enhancing the aircraft's stealth capabilities.

Sweden's Gripen fighter jet is primarily composed of carbon fiber composite structures, accounting for 25% of the airframe's weight, and also uses fiberglass composites and aramid fiber composites. While its design is not as stealth-oriented as some other fourth-generation fighters, the jet's small size and reduced feature inlets lower its overall radar cross-section.

Part 3:

Application of Carbon Fiber Composites in Military Missiles

Warheads and Nozzles
The strong yet lightweight characteristics of carbon fiber composites make them highly desirable in the missile field. Initially, they were primarily used in the warhead sections and solid rocket motor nozzles of missiles. This not only saves weight and reduces costs but also increases the missile's structural strength, extends its range, and improves targeting accuracy.

China's famous Dongfeng-31 missile uses a carbon fiber composite warhead shell to improve missile performance by reducing the weight of the warhead, thereby enhancing its range and accuracy. In the Dongfeng-41 missile, the proportion of carbon fiber composites used is significantly increased, with the missile's outer shell also switched to carbon fiber composites, which further enhances performance, extending its range, allowing it to carry more warheads, and improving accuracy.

The U.S. Tomahawk cruise missile uses carbon fiber composites in the warhead and nozzle sections, improving its performance and combat effectiveness.


Rocket Shells and Launch Tubes
In addition to warheads and nozzles, rocket shells and launch tubes are also starting to use carbon fiber composites. China's Dongfeng-31 missile utilizes a carbon fiber composite warhead shell, and in the Dongfeng-41 missile, the proportion of carbon fiber composites is significantly increased, with the outer shell also switched to carbon fiber composites, leading to enhanced performance, longer range, the ability to carry more warheads, and improved accuracy.

Submarine-Launched and Air-Launched Missiles
Submarine-launched missiles and air-launched missiles are even more sensitive to missile weight, leading to a higher proportion of carbon fiber composites being used. By reducing the weight of air-launched missiles, aircraft can carry more missiles, reducing the aircraft's load, and increasing the missile's range and accuracy. For example, France's Exocet anti-ship missile uses carbon fiber composites in some of its structures, enhancing the missile's performance and compatibility.

Part 4:

Application of Carbon Fiber Composites in Drones

Drones are highly sensitive to weight and cost, and the use of carbon fiber composites can bring significant economic benefits and performance improvements. The U.S. Global Hawk drone has a carbon fiber composite usage rate of up to 65%. China's Cloud Shadow drone uses carbon fiber composites in 60% of its structure, while the U.S. Predator and Shadow drones have composite material usage rates exceeding 90%. Similarly, China's Rainbow drone has a composite material usage rate of over 80%.

Extensive use of carbon fiber composites in drones can reduce airframe weight, improve endurance, and increase payload capacity. For example, Israel's Heron drone uses carbon fiber composites to construct its airframe, giving it long endurance and high payload capabilities, which have proven to be highly effective in reconnaissance and surveillance missions.

Part 5:
Application of Carbon Fiber Composites in Graphite Bombs

During the Iraq War, graphite bombs garnered significant attention. The fine filaments released by these bombs are made from highly conductive carbon fiber, which can be specially modified to enhance their conductivity. After exploding, these carbon fiber filaments can drape over power lines, causing short circuits and leading to local power grid failure. Once the power grid is disrupted, local communications, lighting, and production are all affected, and recovery is difficult in a short time. For example, during the Kosovo War, NATO forces used graphite bombs to attack the power infrastructure of Yugoslavia, resulting in widespread blackouts and severely impacting the country's war capabilities.


Part 6:
Application of Carbon Fiber Composites in Specialized Protective Gear

Bulletproof Vests
Although the current mainstream bulletproof vests are not made from carbon fiber materials, the declining production costs of carbon fiber make its superior performance increasingly attractive. Carbon fiber can be used as fabric for bulletproof vests, offering advantages such as lightweight, high structural strength, and good thermal conductivity. When a bullet strikes the vest, the material can quickly disperse the force and conduct heat, reducing localized damage. Carbon fiber composites can also be used as core materials for bulletproof vests, such as protective plates and bulletproof helmets. For example, some special forces have begun testing bulletproof vests and helmets made from carbon fiber composites, which reduce the soldiers' load while maintaining protective performance, thereby enhancing their mobility.

Thermal Protective Clothing
Combining carbon fiber with aerogel materials can produce highly effective thermal protective clothing, protecting soldiers in high-temperature environments and improving their survival chances in fires. Carbon fiber itself has good thermal conductivity, which helps disperse heat and prevents localized overheating, while aerogels can effectively insulate against heat. For instance, in firefighting and emergency rescue, thermal protective clothing made from carbon fiber composites is already being used to provide better protection for rescue personnel.

Electromagnetic Protective Clothing
Carbon fiber inherently has good conductivity, which allows it to shield against electromagnetic waves. To enhance the shielding effect, special components are often added to the carbon fiber, significantly improving its ability to protect against electromagnetic radiation and preventing harm to soldiers. For example, in electronic warfare and communications, soldiers need to wear electromagnetic protective clothing to shield themselves from electromagnetic radiation.


Part 7:

Development Trends of Carbon Fiber Composites in the Military Industry

Expanding Application Range
With continuous technological advancements, the application range of carbon fiber composites in the military field is expected to broaden. In addition to military aircraft, missiles, drones, and specialized protective clothing, future applications will include naval vessels, tanks, and armored vehicles. For instance, some new naval vessels are starting to use carbon fiber composites in their superstructures to lower the center of gravity, improve stability, and enhance stealth capabilities.

Increasing Performance
Ongoing improvements in the manufacturing processes and performance of carbon fiber composites will enhance their strength, modulus, corrosion resistance, and fatigue resistance to meet higher military demands. Additionally, new carbon fiber composites with specialized functions, such as self-healing and intelligent sensing, are being developed. For example, researchers are exploring carbon fiber composites with self-healing capabilities, allowing materials to automatically repair themselves when damaged, thus increasing the reliability and lifespan of equipment.

Decreasing Costs
As carbon fiber production technology matures and achieves economies of scale, costs will continue to decrease. This will enable more weaponry and equipment to incorporate carbon fiber composites, enhancing performance and combat effectiveness. For example, with advancements in carbon fiber production technology, the price of carbon fiber is gradually falling, creating conditions for the widespread application of carbon fiber composites in the military industry.

Conclusion
炭素繊維複合材は、その優れた性能により軍事産業で重要な役割を果たしています。軍用航空機、ミサイル、ドローン、グラファイト爆弾、特殊防護服への応用により、兵器の性能が向上し、コストが削減され、戦闘効果が強化されました。炭素繊維複合材は、将来、軍事分野でさらに重要な役割を果たすと考えられています。