Refractory Metals

Refractory metals are a class of metals extraordinarily resistant to heat, wear, and corrosion. These properties make them useful in many applications. Household incandescent bulbs contain refractory metals in their tungsten filaments, and nearly all manufactured goods, particularly those containing metal or electronics, contain or were produced using refractory metals.
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metals with melting points >1,750oC, although this definition varies. Some people use >1,900oC and others use any metal with a melting point above Iron, Fe, Nickel, Ni and Cobalt, Co. Refractory metals include, Tungsten, W, Tantalum, Ta, Molybdenum, Mo, Niobium, Nb, and Zirconium, Zr. Regulators - devices that take a varying input and produce a controlled output. Electronic regulators may for example be, voltage regulators or current regulators, or gas systems may have pressure regulators.