Why can titanium alloy become the core material of the aerospace industry?

Why can titanium alloy become the core material of the aerospace industry?

Titanium alloy has low density, high specific strength, good corrosion resistance, low thermal conductivity, non-toxic and non-magnetic, weldable, good biocompatibility, decorative surface and other characteristics, is a lightweight high-strength corrosion resistant structural material, has a wide range of application prospects in weapons and equipment, and has been widely used in aviation, aerospace, chemical, petroleum, electric power, medical, construction, sporting goods and other fields. Titanium Rod Medical，High Purity Titanium Round Target，，Grade 2 Commercial Pure Titanium Foils

The reasons are mainly analyzed from the following aspects:

1. Excellent characteristics of titanium

(1) High strength: 1.3 times of aluminum alloy, 1.6 times of magnesium alloy, 3.5 times of stainless steel, the champion of metal materials.

(2) High thermal strength: the use temperature is several hundred degrees higher than aluminum alloy, and it can work for a long time at a temperature of 450 ~ 500 ° C.

(3) Good corrosion resistance: acid resistance, alkali resistance, atmospheric corrosion resistance, pitting corrosion, stress corrosion resistance is particularly strong.

(4) Good low temperature performance: titanium alloy TA7 with very low gap elements can maintain a certain plasticity at -253 ° C.

(5) Large chemical activity: high chemical activity at high temperatures, easily react with gas impurities such as hydrogen and oxygen in the air to generate a hardened layer.

(6) Small thermal conductivity, small elastic modulus

2. Aviation Application of Titanium Alloy

Titanium material is light weight, strong and high temperature resistant, especially suitable for the manufacture of aircraft and various spacecraft. About three-quarters of the world's titanium and titanium alloys are used in the aerospace industry. Many parts originally made of aluminum alloy have been converted to titanium alloy. It is mainly used in aircraft and engine manufacturing materials, such as forged titanium fans, compressor discs and blades, engine covers, exhaust devices and other parts of the aircraft girder frame and other structural frame. The spacecraft mainly uses the high specific strength, corrosion resistance and low temperature resistance of titanium alloy to manufacture various pressure vessels, fuel tanks, fasteners, instrument straps, frames and rocket shells. Artificial Earth satellites, lunar modules, manned spacecraft and space shuttles also use titanium alloy plate welds.

3.Specific Reasons

The top speed of modern aircraft has reached 2.7 times the speed of sound. Flying at supersonic speeds that fast would cause the plane to rub against the air and generate a lot of heat. When the flight speed reaches 2.2 times the speed of sound, the aluminum alloy cannot withstand, and the low-pressure compressor discs and blades must be made of heat-resistant titanium alloy. As one of the main structural materials of aircraft body structure and aircraft engine, the application level of titanium alloy is one of the important indicators to measure the advanced degree of aircraft material selection, and it is an important aspect that affects the tactical performance of aircraft. Using titanium alloy instead of stainless steel to make high-pressure compressor discs and blades can reduce the weight of the structure. For every 10 percent reduction in weight, the plane saves 4 percent in fuel. For rockets, every 1kg of weight reduction can increase the range of 15km.