On November 8, 2022, the 14th China Air Show opened in Zhuhai. With the roar of the engine, a diamond formation of four J-20 aircraft passed from low altitude. In the solo performance, the J-20 completed the "small radius sharp turn", "pulling green onions in dry land" and other actions in one minute, and the following "barrel roll" and "roll" were even more impressive to the audience. The so-called "layman watch the bustle, and the layman watch the doorway". The "barrel roll" and "roll" are just "a small test" for the J-20. What really amazes aviation experts at home and abroad is the seemingly inconspicuous "small radius sharp turn", "dry land pulling green onions" and other actions. To complete such actions in high-speed flight, the fighter needs not only excellent aerodynamic design and flight attitude control ability, but also a pair of "steel ribs and iron bones" - the fuselage structure of the fighter usually bears 9 times of gravity acceleration when the fighter is carrying out heavy overload maneuvers; In aircraft design, about 50% redundancy should be reserved on this basis. This means that the fuselage structure of the J-20 needs to bear the force generated by hundreds of tons of mass when performing "small radius sharp turn", "dry land pulling green onions" and other actions. The key of the J-20 is its "tough" fuselage structural material. The fuselage structural material, as the name implies, is the structural material that bears the aerodynamic force of the fighter during flight and maintains the aerodynamic shape. The fuselage structural material with excellent performance is an indispensable part of an excellent fighter, and is also the "hard backbone" for the fighter to win the battle. "One generation of materials, one generation of fighter" has been more than 100 years since the Wright brothers invented the aircraft. In this process, materials and aircraft continue to develop under the mutual promotion. The so-called "one generation of materials, one generation of fighter aircraft" is the true portrayal of the history of military aviation in the world. In general, the development of fighter fuselage structural materials has gone through four stages: the first stage was from 1903 to 1910. During this period, the aircraft structural materials were mainly wood and cloth. Wood builds the fuselage frame of the aircraft, and canvas provides the aerodynamic shape for the aircraft. As a structural material, wood has gained long-term vitality with its ultra-light weight and low density. Until the Second World War, wood was still used in some fighter planes. Its typical representative is the British "De Havilan-Mosquito Fighter-Bomber". This fighter has the reputation of "Wood Miracle", is as light as a swallow, and has excellent performance. It is a quite distinctive model in the Royal Air Force. The second stage was from 1910 to 1949. The fuselage material at this stage is mainly steel-aluminum. High-strength steel is often used as the main load-bearing fuselage frame structure, and aluminum alloy is used for fuselage skin. The strength, structural stiffness and ballistic resistance of the aircraft fuselage made of steel-aluminum materials have made a qualitative leap over that of the wood-textile structure. In World War II, the main fighter aircraft models, such as the P51 Mustang and F6F Hellcat of the United States, the Spitfire of the United Kingdom and the MeisseSchmidt Bf-109 fighter of Germany, all adopted steel-aluminum structure without exception. The third stage was from 1950 to 1979. The fuselage materials in this period are mainly steel, aluminum and titanium. In Naigao