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Titanium is a chemical element with the symbol Ti. It has a low density and is a strong, lustrous, corrosion-resistant (including sea water, aqua regia and chlorine) transition metal with a silvercolor. The two most useful properties of the metal form are corrosion resistance and the highest strength-to-weight ratio of any metal. In its unalloyed condition, titanium is as strong as some steels, but 45% lighter.
Titanium can be alloyed with iron, aluminum, vanadium, molybdenum, among other elements, to produce strong lightweight alloys for aerospace (jet engines, missiles, and spacecraft), military, industrial process (chemicals and petro-chemicals, desalination plants, pulp, and paper), automotive, agri-food, medical prostheses, orthopedicim plants, dental and endodontic instruments and files, dental implants,sporting goods, jewelry, mobile phones, and other applications.
Tungsten is a chemical element with the chemical symbol W. A hard, rare metal under standard conditions when uncombined. It is remarkable for its robustness, especially the fact that it has the highest melting point of all the non-alloyed metals and the second highest of all the elements after carbon. Also remarkable is its high density of 19.3 times that of water, comparable to that of uranium and gold, and much higher (about 1.7 times) than that of lead.
The unalloyed elemental form is used mainly in electrical applications. Tungsten's many alloys have numerous applications,most notably in incandescent light bulb filaments, X-ray tubes (as both the filament and target), electrodes in TIG welding, and superalloys. Tungsten's hardness and high density give it military applications in penetrating projectiles.
Molybdenum is a chemical element with the symbol Mo. In its pure form, molybdenum is a silvery-grey metal.
It has a melting point of 2,623 °C (4,753 °F); of the naturally occurring elements, only tantalum, osmium, rhenium, tungsten, and carbon have higher melting points.
It has one ofthe lowest coefficients of thermal expansion among commercially used metals.
Industrially, molybdenum and its alloys are used in high-pressure and high-temperature and coating applications.
Tantalum is a chemical element with the symbol Ta. Tantalum is dense, ductile, very hard, easily fabricated, and highly conductive of heat and electricity. The metal is renowned for its resistance to corrosion by acids; in fact, at temperatures below 150 °C tantalum is almost completely immune to attack by the normally aggressive aqua regia. It can bedissolved with hydrofluoric acid or acidic solutions containing the fluorideion and sulfur trioxide, as well as with a solution of potassium hydroxide. Tantalum's high melting point of 3017 °C (boiling point 5458 °C) is exceededonly by tungsten, rhenium and osmium for metals, and carbon.
It is part of the refractory metals group,which are widely used as minor component in alloys. The chemical inertness of tantalum makes it a valuable substance for laboratory equipment and capacitors in electronic equipment such as mobile phones, DVD players, video game systemsand computers.
Niobium is a chemical element with the symbol Nb. It is a soft, ductile transition metal. Niobium has physical and chemical properties similar to those of the element tantalum.
The temperature stability of niobium-containing superalloys is important for its use in jet and rocket engines. Niobium is used in various superconducting materials. The sesuper conducting alloys, also containing titanium and tin, are widely used in the superconducting magnets of MRI scanners. Other applications of niobium include its use in welding, nuclear industries, electronics, optics, numismatics and jewelry. |
