Titanium and titanium alloys have become one of the most important metals in industry and are widely used in national industry due to their high specific strength, good heat resistance and good corrosion resistance. Industrial pure titanium is the most widely used titanium and titanium alloy materials because of its low cost and easy production. Industrial pure titanium plate has excellent performance, and is easy to weld and braze. It has been widely used to manufacture aircraft and engine parts, such as inner skin of aircraft engine room, corrugated plate, firewall, etc. It is widely used in aerospace, ship and vehicle, electric power, chemical equipment, bioengineering and other fields. Industrial pure titanium is widely used because of its low density, high strength, good corrosion resistance and welding performance. The specifications include thick plate, thin plate, bar, wire, pipe, coil, forging and casting.

Properties of titanium alloys

Titanium is a new type of metal. Its properties are related to the content of impurities such as carbon, ammonia, hydrogen and oxygen. The impurity content of the purest titanium iodide does not exceed 0.1%, but its strength is low and its plasticity is high. The properties of 99.5% industrial pure titanium are: density p=0.45g/cm ', melting point 1725 ° C, thermal conductivity=15.24W/(m.K), tensile strength ob=539MPa, elongation 6=25%, reduction of area 4=25%, elastic modulus E=1.078x105MPa, hardness HB195.
(1) High strength
The density of titanium alloy is generally about 4.5g/cm ', which is only 60% of that of steel. The strength of pure titanium is close to that of ordinary steel. Some high-strength titanium alloys exceed the strength of many alloy structural steels. Therefore, the specific strength (strength/density) of titanium alloy is far greater than that of other metal structural materials, which can produce parts with high unit strength, good rigidity and high quality. At present, titanium alloy is used for engine components, framework, skin, fasteners and landing gear of aircraft.
(2) High thermal strength
The service temperature is several hundred centigrade higher than that of aluminum alloy, and the required strength can still be maintained at medium temperature. The titanium alloy can work at 450~500 ° C for a long time. The specific strength of these two types of titanium alloys is still very high at 150~500 ° C in China, while the specific strength of aluminum alloy decreases significantly at 150 ° C. The working temperature of titanium alloy can reach 500 ° C, while that of aluminum alloy is below 200 ° C.
(3) Good corrosion resistance
Titanium alloy works in humid atmosphere and seawater medium, and its corrosion resistance is much better than stainless steel. It has strong resistance to pitting corrosion, acid corrosion and stress corrosion, and has excellent corrosion resistance to alkali, ammonia, oxygen organic substances, nitric acid, sulfuric acid, etc. However, titanium has poor corrosion resistance to reducing oxygen and chromium salt medium.
(4) Good low-temperature performance
Titanium can still maintain its mechanical properties at low and ultra-low temperatures. Titanium alloys, such as TA7, which have good low-temperature performance and extremely low risk elements, can still maintain certain plasticity at - 253 ° C.
Therefore, titanium alloy is also an important low temperature structural material.
(5) High chemical activity
The chemical activity of titanium is high, which is similar to that of O, N H. Co, co, water vapor: ammonia gas produces strong chemical reaction. The carbon content is greater than 2%, hard TIC will be formed in titanium alloy; At higher temperature, TN hard surface will also be formed under the action of gas N; When the temperature is above 600 ° C, titanium absorbs oxygen to form a hardened layer with high hardness; The embrittlement layer will also be formed when the hydrogen content increases. The depth of hard and brittle surface layer produced by absorbing gas can reach 0.1-0.15mm, and the hardening degree is 20%~30%. The chemical affinity of titanium is also large, and it is easy to stick to the friction surface Appearances.
(6) Small thermal conductivity and elastic modulus
Thermal conductivity of titanium=15.24W/(m. K)

In addition to the mechanical properties of titanium alloy at room temperature according to Table-1, other requirements can be used to produce and process titanium and titanium alloy pipes according to any of API Spec 5CT and ASTM B861Q/SY-TGRC45-2013Q/DGJ0004-2013 standards.