Titanium alloy applications

Titanium alloy has high strength and low density, good mechanical properties, good toughness and corrosion resistance. In addition, titanium alloys have poor processing properties and are difficult to cut. In hot working, it is very easy to absorb impurities such as hydrogen, oxygen, nitrogen and carbon. There is also poor wear resistance and complex production process. The industrial production of titanium began in 1948. The development of the aviation industry requires the titanium industry to grow at an average annual rate of about 8%. The annual production of titanium alloy processing materials in the world has reached over 40000 tons, with nearly 30 titanium alloy grades. The most widely used titanium alloys are Ti-6Al-4V (TC4), Ti-5Al-2.5Sn (TA7), and industrial pure titanium (TA1, TA2, and TA3).
Titanium alloy is mainly used for making aircraft engine compressor components, followed by structural components for rockets, missiles, and high-speed aircraft. In the mid-1960s, titanium and its alloys were widely used in general industries, such as making electrodes in the electrolysis industry, condensers in power plants, heaters for petroleum refining and seawater desalination, and environmental pollution control devices. Titanium and its alloys have become a corrosion-resistant structural material. In addition, it is also used for the production of hydrogen storage materials and shape memory alloys.
China began research on titanium and titanium alloys in 1956; In the mid-1960s, industrial production of titanium materials began and TB2 alloy was developed.
Titanium alloy is a new important structural material used in the aviation space industry. Its specific gravity, strength and service temperature are between aluminum and steel, but its strength is higher than aluminum and steel, and it has excellent seawater corrosion resistance and ultra-low temperature performance. In 1950, the United States first used non load-bearing components such as rear fuselage insulation panels, wind shields, and tail shields on F-84 fighter bombers. Since the 1960s, the use of titanium alloy has shifted from the rear fuselage to the middle fuselage, partially replacing structural steel to manufacture important load-bearing components such as diaphragms, beams, and flap slides. The use of titanium alloy in military aircraft has rapidly increased, reaching 20% to 25% of the structural weight of the aircraft. Since the 1970s, civilian aircraft have started to use a large amount of titanium alloy, such as the Boeing 747 aircraft, which uses over 3640 kilograms of titanium. Titanium is mainly used in aircraft with Mach numbers greater than 2.5 to replace steel and reduce structural weight. For example, the US SR-71 high-altitude high-speed reconnaissance aircraft (with a flight Mach number of 3 and a flight altitude of 26212 meters), which accounts for 93% of the aircraft's structural weight, is known as the "all titanium" aircraft. When the thrust to weight ratio of an aircraft engine increases from 4-6 to 8-10, and the outlet temperature of the compressor correspondingly increases from 200-300 ° C to 500-600 ° C, the low-pressure compressor discs and blades originally made of aluminum must be replaced with titanium alloy, or titanium alloy must be used to replace stainless steel to manufacture high-pressure compressor discs and blades, in order to reduce structural weight. In the 1970s, the amount of titanium alloy used in aviation engines generally accounted for 20% to 30% of the total structural weight, mainly used for manufacturing compressor components, such as forged titanium fans, compressor discs and blades, cast titanium compressor casings, intermediate casings, bearing shells, etc. Spacecraft mainly utilize the high specific strength, corrosion resistance, and low-temperature resistance of titanium alloy to manufacture various pressure vessels, fuel storage tanks, fasteners, instrument straps, frames, and rocket shells. Artificial Earth Satellite, Lunar Module