Many practical applications of Tungsten are based on its high melting point and density and its low vapor pressure. Tungsten is an excellent material for high vacuum technology, dimensional stability, glass seals and furnace construction. In addition, Tungsten’s high density gives it a capacity to absorb radioactive radiation. Tungsten has found wide use as additives to steel to enhance physical properties and an alloy with nickel, copper and iron to provide high density machinable materials.