Titanium powder and its application
What is titanium powder
Titanium powder refers to the metal titanium particle group with the size less than 1mm, which is a loose material. Its performance combines the characteristics of titanium matrix and the commonness of powder. Like other powders, the properties of titanium powder include chemical, physical and technological properties of the powder. However, titanium powder and other powders have a common physical property that they have a large specific surface area, so titanium powder also has a large surface free energy. Therefore, titanium powder is more active than metal titanium, more likely to react with other elements or compounds, more easily oxidized, flammable and explosive, and belongs to a dangerous product. Its purity and various properties largely depend on the preparation method and technological conditions.
Titanium powder is silver gray powder foam, which can burn in nitrogen with high melting point. Titanium can be hydrogenated by adding hydrogen at high temperature in vacuum. After inhaling a large amount of hydrogen, titanium hydride becomes titanium hydride. Titanium hydride is easy to embrittle and easily made into powder foam. It is a common method for mass production of titanium powder at present.
The hydrogen content of titanium hydride powder is generally 4%, silver is dark gray, and hydrogen will be released under high temperature. At present, the application of this technology to make "foam aluminum" titanium hydride powder, because of the hydrogen content, needs to be made into pure titanium powder under high temperature and vacuum, and a lot of time is spent vacuuming to reduce it to titanium powder. Titanium powder is stable at room temperature and has strong combining ability at high temperature. It can combine with oxygen, carbon, nitrogen, hydrogen and many other elements. Pure titanium powder can absorb air at high temperature, so pure titanium powder is used as "getter" in electronic industry.
What is the purity of titanium powder
Titanium powder includes titanium content and impurity content. The purity of titanium powder is related to its particle size. For products of the same specification, the smaller the particle size, the lower the purity. Generally, the (coarse) titanium powder with titanium content greater than (or equal to) 99% or close to 99% is called a grade product (if it is a titanium alloy powder, the alloy composition should be included), and the product with lower purity is called a substandard product. In addition to the requirements for special use, the grade of titanium powder generally requires the oxygen content (the same as the titanium content). That is, the lower the oxygen content, the higher the quality. Among them, those with oxygen content less than 0.15% are often called high-quality titanium powder.
What are the uses of titanium powder
Titanium powder is widely used. Grade titanium powder has different uses according to different purity and particle size. It is mainly used as raw material for powder metallurgy to make titanium or titanium containing alloy. Other applications are used as electric vacuum getter, raw material of electric vacuum solid gong source, and surface coating material. Titanium filler for plastics and raw materials of various titanium compounds (such as TiB2, TiN, TiC, etc.).
Dihydrogenated titanium powder can be used as welding agent for ceramics and metals, pure hydrogen source material and powder metallurgy sintering catalyst.
Titanium powder is also used in "metal additives" as a titanium agent. As an additive, titanium powder can be divided into titanium content: Ti ≥ 88% Ti ≥ 90% Ti ≥ 92% Ti ≥ 95% Ti ≥ 97% Ti ≥ 98%. The particle size is divided into 40 meshes, 60 meshes, 80 meshes and 100 meshes, which can be used as "titanium agent".
The substandard titanium powder is mainly used as the grain refiner of cast aluminum and the flower deflagrant for fireworks and ceremonies. Titanium powder will emit white sparks during combustion. Titanium powder is flammable in case of open fire and strong friction. 100 mesh titanium powder is usually used for outdoor fireworks, and 200 mesh titanium powder is used for indoor cold light fireworks. The higher the purity, the whiter the spark.