Titanium And Titanium Alloys: Widespread Application And Future Challenges

Discovery and industrial application

Titanium was discovered by Gregor of Britain in 1791, and then in 1795, German chemist Klaprus named this newly discovered metal after the Greek god Titans, which is translated into “titanium” in Chinese. This metal is abundant on the earth, with as many as 140 known titanium minerals, but ilmenite and rutile are mainly used in industry. China’s ilmenite reserves lead the world, accounting for 28%.

Titanium is widely used in many fields due to its unique properties, such as high and low temperature resistance, strong acid and alkali resistance, high strength and low density. For example, it was selected by NASA as a special material for rockets and satellites, and it also plays a key role in major projects such as my country’s Yutu, J-20 and Shandong aircraft carrier. After entering the civilian field in the 1980s, titanium was hailed as the “honorary metal king” in the food industry because of its natural antibacterial and biophilic properties.

China’s titanium industry started in the 1950s, and sponge titanium and titanium processing plants were built in the mid-1960s, marking China’s rise in the titanium industry. After entering the 21st century, China’s titanium industry has ushered in new development opportunities, and its production capacity has ranked among the top in the world.

Pure titanium and titanium alloys

Pure titanium, also known as industrial pure titanium or commercial pure titanium, is graded according to the content of impurity elements. It exhibits excellent stamping process performance and welding performance, and is insensitive to heat treatment and tissue type. Under the condition of meeting a certain plasticity, pure titanium also has a certain strength, which is mainly affected by the content of interstitial elements oxygen and nitrogen. For example, the performance indicators of 99.5% industrial pure titanium are as follows: density is 4.5g/cm³, melting point reaches 1800°C, thermal conductivity is 15.24W/(M.K), tensile strength σb is 539MPa, elongation is 25%, cross-sectional shrinkage is 25%, elastic modulus is 1.078×10⁵MPa, and hardness is HB195.

Titanium alloy is an alloy composed of other elements added to titanium. Although the history of this metal is relatively short, with only sixty or seventy years of discovery, titanium alloy has occupied an indispensable position in key components such as aircraft engines, rockets, and missiles due to its light weight, high strength, high temperature resistance and corrosion resistance.

It is worth noting that titanium has two isomorphous crystal structures. Below 882°C, it presents a close-packed hexagonal crystal lattice structure, called α titanium; above 882°C, it transforms into a body-centered cubic lattice structure, called β titanium. By cleverly utilizing the characteristics of these two structures and adding appropriate alloying elements, scientists can gradually change the phase transition temperature and phase fraction content to obtain titanium alloys with different organizational characteristics.

These alloying elements can also be classified according to their effect on the phase transition temperature. For example, elements that can stabilize the α phase and increase the phase transition temperature are called α-stabilizing elements, including aluminum, magnesium, oxygen and nitrogen. Among them, aluminum is a key alloying element in titanium alloys, which can significantly improve the room temperature and high temperature strength of the alloy while reducing the specific gravity and increasing the elastic modulus. On the other hand, elements that can stabilize the β phase and reduce the phase transition temperature are called β-stabilizing elements, which can be divided into isomorphous and eutectoid types. In addition, there are some neutral elements that have little effect on the phase transition temperature, such as zirconium and tin.

Analysis of titanium alloy grades

The following will analyze common grades in detail:

TA1 (American Standard Gr1) grade: TA1 is known for its softness and ductility. It has excellent formability, corrosion resistance and high impact toughness, and is the preferred material for applications that pursue easy formability. TA1 grade titanium is often used to make titanium plates and titanium pipes.

TA2 (American Standard Gr2) Grade: TA2 grade titanium is favored for its wide availability and diverse properties. It shares many of the premium properties of TA1 grade titanium alloy and is slightly stronger on top of that. This grade combines good weldability, strength, ductility and formability.

TA3 (American Standard Gr3) Grade: Although TA3 grade is relatively less used among commercially pure titanium grades, its mechanical properties cannot be ignored. Compared with TA1 and TA2, it has higher strength while maintaining similar ductility.

TA4 (American Standard Gr4) Grade: TA4 grade titanium is known as the toughest of the four commercially pure titanium grades. Its corrosion resistance and high strength show unique advantages in applications that require high definition.

TA9 (American Standard Gr7) Grade: Transformed from pure titanium to an alloy with properties comparable to TA2 grade by adding the interstitial element palladium. In addition, it also has excellent weldability and corrosion resistance.

I: Application of titanium and titanium alloys

Alkali and salt making industry

In the alkali making industry, the emergence of titanium refrigerators has greatly improved the shortcomings of traditional cooling processes and effectively solved the problem of unqualified chlorine gas output quality. At the same time, the application of titanium alloy refrigerators has completely changed the production pattern of the chlor-alkali industry. In the salt making industry, vacuum salt making has become a more advanced process. However, the high-temperature concentrated brine produced in this process will cause serious damage to the equipment with carbon steel structure. By using titanium-steel composite structure to construct the heating chamber and evaporation chamber, the formation of salt scale can be effectively prevented, thereby improving the quality of salt making.

Aviation and aerospace industry

Titanium alloys are widely used in the aviation field, covering many key parts of aircraft structure and engine structure. For example, aircraft structural parts such as landing gear parts, frames, beams, fuselage skins and heat shields are all made of titanium alloy materials. Titanium alloys are widely used in the aviation and aerospace fields due to their high strength and high temperature resistance. For example, in aerospace vehicles, the working conditions faced are extremely harsh, requiring materials to have excellent properties. For this reason, titanium alloys are unique among many materials and are widely used in the aerospace field. In aerospace equipment, titanium alloys have demonstrated their unique advantages. For example, in the Apollo program of the United States in the 1960s, the spacecraft’s double cabin and closed cabin wing beams and ribs were made of Ti-5Al-2.5Sn titanium alloy.

Ship field

Titanium and titanium alloys provide excellent corrosion resistance and high strength in ship manufacturing, and are widely used in nuclear submarines, submersibles, atomic icebreakers and other ships. For example, the US “Sea Cliff” submersible is equipped with titanium observation cabins and control cabins.

II: Challenges and future of titanium and titanium alloys

Existing problems

Although titanium and titanium alloys have made remarkable achievements in many fields, the problems that come with them are becoming increasingly prominent. The titanium industry faces insufficient production, high costs and performance challenges, especially in the need to improve high-temperature creep for further application.

Future prospects

Titanium alloys have great potential in the automotive and other industrial fields. Reducing costs and increasing production will expand their application range. Once high-end titanium alloys are manufactured at low cost, their application areas will be greatly expanded.

Keywords：
titanium alloy titanium alloy ti 6al 4v titanium alloy 6al 4v titanium alloy price titanium alloy bar titanium alloy sheet titanium alloy plates titanium alloy rod titanium alloy manufacturers titanium alloy suppliers titanium alloy material titanium alloy company titanium alloy factory buy titanium alloy titanium alloy for sale titanium alloy price per kg titanium alloy products titanium alloy cost per kg