(1) reduce the structure weight, improve the efficiency of the structure, advanced performance, such as supersonic aircraft lighter aircraft with low structure weight coefficient (i.e., the body weight/structure plane normal take-off weight), and the intensity of titanium alloy is close to the characteristics of strong steel but density is small, instead of structural steel and high temperature alloy, can greatly reduce the structure weight, also can save cost; Take the engine as an example. Statistics show that the cost of using an aircraft engine can be reduced by about 220-440 dollars for every kilogram of quality reduction.
(2) as to meet the requirements of the use of high temperature parts: titanium alloy has good heat resistance characteristics, such as commonly used Ti 6 al 4 v can long-term work under 350 ℃, so in the heat of the airplane parts (such as after the fuselage, etc.) can be replaced by high temperature performance cannot meet the requirements of aluminium alloy; TC11 can long-term work under 500 ℃, in compressor parts of the engine can replace high temperature alloy and stainless steel.
(3) in line with the requirements of composite material structure matching: in order to reduce the structure weight and meet the requirements of stealth, advanced aircraft use a large number of composite materials, titanium alloy and composite material strength, stiffness match well, can get a good weight reduction effect. At the same time, because the potential of the two is relatively close, it is not easy to produce galvanic corrosion, so the corresponding parts of the structural parts and fasteners should be titanium alloy.
(4) meet the requirements of high corrosion resistance and long life: titanium alloy has a high fatigue life and excellent corrosion resistance, can improve the corrosion resistance and life of the structure, to meet the requirements of advanced aircraft, engine high reliability and long life.
