Titanium alloys are mainly used to make compressor parts for aircraft engines, followed by structural parts for rockets, missiles and high-speed aircraft. By the mid-1960s, titanium and its alloys had been used in general industry, for making electrodes for the electrolytic industry, condensers for power stations, heaters for oil refining and desalination, and environmental pollution control devices. Titanium and its alloys have become a kind of corrosion resistant structural material. In addition, it is also used to produce hydrogen storage materials and shape memory alloys. China began to study titanium and titanium alloys in 1956. In the mid-1960s, the industrial production of titanium began and TB2 alloy was developed. Titanium alloy is a new important structural material used in the aerospace industry. Its specific gravity, strength and service temperature are between aluminum and steel, but its specific strength is high and it has excellent seawater corrosion resistance and ultra-low temperature performance. In 1950, the United States first used the f-84 fighter-bomber as a rear fuselage heat shield, wind shield, tail shield and other non-load-bearing components. Starting from the 1960s, the use of titanium alloy moved from the rear fuselage to the middle fuselage, partially replacing the structural steel to manufacture important bearing components such as frame, beam and flap slide rail. The amount of titanium alloy used in military aircraft increases rapidly, up to 20% ~ 25% of the weight of aircraft structure.
The development of high pulse thrust-to-weight ratio engines for advanced space rocket technology products requires the use of titanium alloys with higher strength and plasticity at low temperatures. For this reason, the Russian "composite materials" joint stock company metal research institute is carrying on the BT6c alloy for this project process determination work cycle. Made the working temperature of the alloy - 200 ℃ from 600 mm die forgings, accumulator is used in the plate, the bearing bracket and blank pipe joint. Ways of reducing the working temperature of the alloy to a 253'C are being explored, one of which is to obtain parts by particle metallurgy. This process can ensure that all parts of the billet have uniform fine crystal structure, and make the performance of the whole billet isotropic. The BT6c alloy particles were prepared by + hot isostatic pressure and roasting in one stage. The strength of the compact billet was 100MPa higher than that of bt5-1kt alloy, and the fatigue performance was higher.
Important issue is to research and development a sigma b > 800 mpa, oxidation temperature of 850 ℃ new nearly alpha alloy, to replace the large stainless steel welded structure. The alloy, which will contain hafnium and niobium, will be characterized by high process plasticity and oxidation resistance at temperatures up to 850'C, with minimal protection during welding, rather than expensive space-siloed welding equipment with a protective atmosphere.
