Titanium parts on fighter jets
In 1950, the United States took the lead in using titanium and titanium alloys on fighter planes - using industrial pure titanium to manufacture non-load-bearing parts such as the rear fuselage heat shield, wind deflector, and tail cover of the F84 fighter. In 1954, Pratt & Whitney of the United States and Rolls-Royce of the United Kingdom used Ti6AI4V alloy to manufacture aero-engine parts. In the mid-1960s, the United States made an all-titanium aircraft YF-12A/SR-71, and the amount of titanium used reached 95% of the structural quality of the aircraft. Due to the excessive use of titanium, it was not economical, and it could not compete with aluminum and did not develop; 60 Since the 1990s, the amount of titanium alloys used in aero-engines has increased year by year, mainly used for fan blades, compressor blades, discs, shafts, casings, etc. Forgings etc.
Table 1 shows the application of titanium alloys in US military aircraft: F-14 accounts for 24%, F-15 accounts for 27%, F-18 accounts for 13%, F-117 accounts for 25%, B-2 accounts for 26%, The fourth-generation fighter F-22 uses 41% titanium, and 36 tons of titanium alloys for the structure, mainly Ti-6AI-4V, Ti-6AI-4VELI, and Ti-62222 alloys. The titanium content of the French Mirage 2000 aircraft accounted for 23%, and the titanium content of the Soviet Cy-27CK fighter aircraft accounted for 18%.
In the early 1960s, China used titanium alloys for the first time in the structure of fighter aircraft. It was first used in the J-7 aircraft. At that time, the total consumption of a single aircraft was less than 10 kg. In 1983, the TC4 titanium alloy dies forgings were used for the important role of the aircraft. bearing member. The "J-10 aircraft project" developed by five units including the Chengdu Aircraft Design Institute of China Aviation Industry First Group Corporation and Chengdu Aircraft Company, which took 20 years of research and development, won the 2006 National Science and Technology Progress Special Award, becoming the second-largest manned space project in China. It is a major scientific research project that has won the national award and special prize. The J-10 is a third-generation fighter with completely independent intellectual property rights. It adopts a large number of new materials, new technologies, and new processes, with advanced performance and a wide range of uses. The first batch of equipment troops has created a precedent for Chinese military aircraft to be produced in small batches and assembled before finalizing the design. It is a major step in China's journey to climb the peak of science and technology.
The use of titanium in the J-10 fighter represents to a large extent the actual level of titanium used in the structure of Chinese fighter aircraft in the 1980s and before, such as the 58-frame vertical tail joint of the fuselage and the fuselage 351 beam and other components. Although the aircraft uses some titanium alloys, which has greatly improved the level of titanium alloys used in the structure of Chinese fighter aircraft, the amount used is still relatively small, less than 2% of the overall structural quality of the aircraft. The main reason is that the performance of domestic titanium alloy materials was unstable, the structure was uneven, and defects such as coarse grains, inclusions, and segregation appeared from time to time. It is revealed that it causes difficulties in production; aircraft factories have backward manufacturing technology, difficult processing, long processing time, low material utilization (about 10% for forgings, about 30% for sheet metal parts), high production costs, and high costs; materials are expensive, Especially thin sheets. Fortunately, these shortcomings have been overcome. Since 2010, the properties of titanium alloys produced in China are completely comparable to those of industrially developed countries.
