Description

�Tungsten not only has the highest melting point but also the lowest vapor pressure of all metals. Hence, tungsten is an excellent material for high-vacuum technology and related applications at the highest temperatures. 2�The low thermal expansion combined with its high melting point and great dimensional stability at high temperature make tungsten a highly suitable material for glass seals. 3�Compared with other heating element materials, the specific resistance of tungsten is relatively low but increases with temperature. The electrical resistance characteristics of tungsten are important for its use in high-temperature furnace construction. 4�Owing to its high density, tungsten has a high absorption capacity for radioactive radiation. Absorption material for X-rays and gamma rays are made of tungsten alloys of high tungsten content with a nickel-iron or a nickel-copper binder phase, which can then be readily machined.