Like Niobium, Tantalum is a heat-tolerant refractory metal with excellent corrosion resistance. Often alloyed with other metals, tantalum is used to make super alloys used in chemical processing, jet engines and nuclear reactors. Its oxidation properties also make it an excellent choice for many electronic applications, including electrolytic capacitors and high-power resistors. Tantalum is also highly bio-compatible and used extensively for medical applications, such as skull plates, hip joints, suture clips and stents.
Used with Alumel® in type K thermocouples and with Constantan in type E thermocouples, Chromel® is made of nickel and chromium.
With an extremely low coefficient of thermal expansion, approximately one-tenth that of carbon steel at temperatures up to 400° F, Invar® is often thought of as the material of choice for low expansion nickel alloy applications. The ability to maintain strength at very low temperatures also makes it the optimum choice for containing some liquid gasses.
Alloy 52 is a nickel-iron alloy with a thermal expansion rate similar to soft glasses and ceramics. Typical applications include voltage regulators, conductors, and glass-to-metal hermetic seals.
Composed of iron, nickel and cobalt, Kovar®1 has thermal expansion characteristics similar to hard glass, making it an excellent choice for glass-to-metal hermetic seals. Kovar® is widely used in the electronics industry.