Tantalum occurs in columbium ores. As the demand for columbium increases, increasing amounts of tantalum concentrates become available. After a difficult and complex separation and reduction process, both metals are obtained in the form of powder. The powder is pressed in dies to form bars which are vacuum sintered by passing high currents through them […]
Tungsten, tantalum, molybdenum, columbium, vanadium, and chromium may be classed as relatively abundant refractory metals; that is, Free World reserves of contained metal are over 100,000 tons for each metal. The first four show promise in a considerably higher temperature range than the last two, and sometimes the term “refractory metals” is used narrowly to […]
Tantalum Hafnium Carbide Alloy (3990℃) Tantalum hafnium carbide alloy (Ta4HfC5) actually refers to tantalum and hafnium pentacarbonate compound, which has the highest melting point among known compounds. It can be considered to be composed of two binary compounds, tantalum carbide (melting point 3983 ℃) and hafnium carbide (melting point 3928℃). Tantalum hafnium carbide alloys are […]
Tungsten is the most plentiful of the refractory metals. However, about half of the world’s reserves are found in China. Korea is another important source along with Bolivia, Portugal, Australia, Thailand, Canada and United States. Despite its resources, the United States still must import most of its consumption. Since the late 70’s the use of […]
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