Tungsten's atomic symbol is W and its atomic number is 74 on the periodic table of elements. Tungsten is a transition metal that has a higher melting point than any other metallic element (6,170 degrees Fahrenheit). At room temperature, the tensile strength of tungsten ranges between 100,000 and 500,000 pounds per square inch (psi). Tungsten's tensile strength, at 1,650 degrees Fahrenheit, is higher than that of any other metal.
Tungsten is used to create steel. Tungsten steel is an alloy, which is a metal that is created by the joining of two or more metals. Tungsten steel contains between one and 20 percent tungsten. The tungsten in tungsten steel increases both the heat resistance and the hardness of the steel. This alloy is designed for applications like high-speed cutting and forming. Many machine forming and cutting attachments such as drill bits and saw blades are made out of this alloy. Many turbine engine manufacturers also make their engines out of tungsten steel. Hand tools such as wrenches that are made out of tool steel usually contain tungsten steel.
Tungsten carbide is created when tungsten is combined with carbon. Many grinding disks, metal cutting and metal forming bits, as well as most armor-piercing ammunition for both heavy and light artillery is constructed out of tungsten carbide. This man-made material is harder than tungsten steel. Tungsten carbide, which is one of the hardest materials known, has a Moh's hardness rating of 9 (out of 10). Only a handful of materials including silicon carbide and diamond are harder than tungsten carbide. Tungsten carbide is about twice as hard as steel. To lower the cost of their tungsten carbide grinding discs, many manufacturers assemble their tungsten carbide grinding discs on steel bases.
Light bulb filaments are made out of tungsten. Incandescent and halogen bulbs can burn at more than 2,000 degrees Fahrenheit. Tungsten is very resistant to heat. Its high melting point makes it the perfect material to use for light bulb filament applications. However, tungsten filaments are very thin and will degrade over time. This is why halogen light bulbs use halogen as a fill gas, which helps to maintain the integrity of the tungsten filament over time.