Other Materials

Tungsten Carbide

Tungsten carbide is a chemical compound containing equal parts of tungsten and carbon atoms. In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes through sintering process. Tungsten carbide is approximately twice as hard as steel, with a Young’s modulus of approximately 530-700 GPa (77,000 to 102,000 ksi), and is double the density of steel: nearly midway between that of lead and gold.

Sintered tungsten carbide cutting tools are very abrasion resistant and can also withstand higher temperatures than standard high-speed steel (HSS) tools. Carbide cutting surfaces are often used for machining through materials such as carbon steel or stainless steel, and in applications where steel tools would wear quickly, such as high-quantity and high-precision production. Because carbide tools maintain a sharp cutting edge better than steel tools, they generally produce a better finish on parts, and their temperature resistance allows faster machining.

Tantalum

Tantalum is a chemical element with the symbol Ta and atomic number 73. It is part of the refractory metals group, which are widely used as minor components in alloys. 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. Tantalum’s high melting point of 3017 °C (boiling point 5458 °C) is exceeded among the elements only by tungsten, rhenium and osmium for metals, and carbon.

The major use for tantalum, as the metal powder, is in the production of electronic components, mainly capacitors and some high-power resistors. Tantalum is also used to produce a variety of alloys that have high melting points, strength, and ductility. Alloyed with other metals, it is also used in making carbide tools for metalworking equipment and in the production of super alloys for jet engine components, chemical process equipment, nuclear reactors, missile parts, heat exchangers, tanks, and vessels.

Niobium

Niobium is a chemical element with the symbol Nb and atomic number 41. Niobium is a light grey, crystalline, and ductile transition metal. Niobium becomes a superconductor at cryogenic temperatures. At atmospheric pressure, it has the highest critical temperature of the elemental superconductors at 9.2. Niobium has the greatest magnetic penetration depth of any element.

Niobium is used in various superconducting materials. These superconducting alloys, also containing titanium and tin, are widely used in the superconducting magnets of MRI scanners. Other applications of niobium include welding, nuclear industries, electronics, optics, numismatics, and jewelry. In the last two applications, the low toxicity and iridescence produced by anodization are highly desired properties. Niobium is considered a technology-critical element.