Steel, an alloy of iron and carbon, comes in many varieties. Mixed with other metals, it takes on different properties. Tungsten was one of the first metals used to improve steel. It adds strength to steel over a wide temperature range.
Metals that have been mixed to obtain materials with new properties are called alloys. Mixing steel with small amounts of other metals, such as vanadium, cobalt and tungsten, contributes strength, hardness and corrosion resistance.
Tungsten, like iron, is a basic chemical element. It stands up to heat better than any other metal, having the highest melting point, 6192 degrees F (3695 C), and the highest tensile strength at temperatures over 3000 F (1650 C). It also expands less than any other pure metal from heat and has high resistance to corrosion.
Cutting tools, such as drill bits, produce great heat from friction. Tungsten, added to steel in amounts varying from 2 to 18 percent (along with small amounts of molybdenum and vanadium), maintains the metal’s strength at high temperatures. Called high-speed steel, it goes into making drill bits, milling bits, saw blades and other tools.
- drill bit image by Greg Pickens from Fotolia.com