For the countries around the world, both of the aviation research and development and manufacture industry are the systems engineering which involve many industries and fields. Especially in the military field, a warplane consists of a huge system components and the key part is the engine. In recent years, the idea of using titanium alloys as the engine material has already become the global consensus. With the continuously improvement of domestic independent research and development technology, Chinese researchers started to realize the development and use of this high-tech material as well. It is worth mentioning that China reserves rich deposits of titanium metal itself. With the promotion and upgrade of titanium alloy technology, many types of new fighters in China will be expected to install the titanium engines in the future to improve the performance level. Why is titanium the best material for the engines? First of all, the high strength of titanium metal is unique among all the metal elements and it surpasses aluminum alloys, magnesium alloys and stainless steels etc. It can work stably in a high temperature environment of 450 ~ 500℃. At the same time, it also has the comprehensive advantages of good corrosion resistance, good low temperature performance, large chemical activity, small thermal conductivity and small elastic modulus. The data show that three-quarters of titanium alloys of global production were used in aerospace industry.
With constant transcending of aviation research and development technology, the requirements for the engines are getting higher and higher. Especially the most significant property -thrust- weight ratio, is the standard specification for a advanced airplane. In jet age, the thrust- weight ratio is normally about 2-3, but now in supersonic age it can reach to 10 and above because of the upgrading of the engine materials. Speaking from the theory of aviation, in order to fully improve the thrust- weight ratio of the engines, weight reduction is the most crucial way. Even though the density of titanium is only 40% that of steels, the strength of them is same. The melting point is 1668℃ which proves that it is the best material for aero engines.
Our country constantly catches up with European and American powers in the engine independent research and development all the time. Especially in the research and development of high temperature resistant titanium alloy material, we gradually shorten the gap with first-world countries. The domestic scientific research team had developed many kind of materials for aero engines use such as TC-4, TC-11, and TC-14. Particularly 550℃ high temperature resistant titanium alloy appeared in the 1990s, which laid a solid foundation for the follow-up research and development of domestic the fourth generation warplanes.
