Producing dense tungsten, and alloys in addition to powder metallurgy methods, there are melting, chemical vapor deposition, physical vapor deposition method.

Consumable Electrode Vacuum Arc Melting

Modern electric arc smelting, melting usually consumable tungsten electrode and the copper and copper alloy arc melting crucible. In a vacuum state, the molten metal is cooled copper crucible inflows (ingot mold) cooled into ingots, the thermal conductivity of copper, the heat transfer is easy, so that the liquid metal contacts to the water-cooled copper crucible rapidly solidified, thus eliminating the tungsten, and copper alloy and the reaction between the crucible. Tungsten metal is melted in the arc flame, electric arc occurs in the upper electrode (consumable) and the lower electrode (copper ingot mold tungsten and its alloys) between. Consumable electrode vacuum arc melting the cathode, the molten metal as the anode.

Tungsten arc melting ingots having a coarse grain structure, therefore, brittle, can be eliminated after the melting heat stress treatment, or adding other elements as an impurity scavenger, and a gap to control the grain size.

Electron Beam Melting

Electron beam melting high purity tungsten and alloys thereof, but not particularly coarse grain, not the pressure processing. Industrially used by the primary electron beam melting and then vacuum consumable arc melting. Electron beam melting tungsten alloy products and the intensity ratio of output arc melting and powder metallurgy products low and plastic - brittle transition temperature close to or slightly above them.

Zone Melting

Electron beam heating method using tungsten, and alloys of zone melting, can be obtained by zone melting high purity tungsten, having a Vickers hardness of 2842-33430, tungsten has also been greatly improved toughness.

By chemical vapor deposition direct production of dense tungsten products are of three types:

(1) Surface Coating: the part or parts of tungsten thin layer deposited on the surface, from corrosion or some functional role;

(2) Composite Material: the development of new materials with excellent mechanical properties;

(3) Shaped Products: a tubular, disc crucible complex shaped products;

Production of chemical vapor deposition of tungsten products, there are three types of methods: (1) thermal decomposition method (2) reduction of hydrogen halide (3) chemical vapor transport "water cycle" method

Difficulty from the production, operation Traditional and Simplified, toxicity, and low cost, quality and other advantages and disadvantages to consider, the current into the main method of industrial production stage hydrogen halide reduction method only. Which is the most widely chloride Hydrogen Reduction of tungsten coatings and composite materials and fluoride Hydrogen Reduction of shaped dense metal products.

O. M. Korolev (Kopojeb) for heating the outer surface of copper deposition process in the airflow rate by diffusion of reactants. With increasing content of WF6, diffusion controlling the kinetically controlled transition. 873K (about 2.4mm / h) and 973K (about 4.6mm / h), respectively, the maximum deposition rate of the WF6 concentration of 30% and 40% is reached.

Preparation of chemical vapor deposition of tungsten products does not require milling and forming stage, the deposition process is not only forming process, but also from the purification effect, can be obtained very high purity, density can reach theoretical density tungsten and tungsten coating products, so this France to get more and more widely used.

The early 1980s, the U.S. super-metal (Ultramet) Company uses fluoride hydrogen reduction of tungsten chemical vapor deposition method for the construction of a large fusion reactor fuel containers seamless tungsten crucible. Its diameter is 330mm, height 553mm, wall thickness of 1.52-2.03mm. Chemical vapor deposition is currently possible to manufacture such a large dense parts of the unique way.


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Tungsten carbide is an extremely hard and durable metal that's used for everything from industrial applications to men's jewelry. A combination of the extremely hard metal tungsten and carbide mixed together with another metal binding agent, tungsten carbide can a hardness of up to 9.5 on the Moh's scale (not very far below diamond, which is the hardest on the scale). Tungsten carbide is also chemically inert, and will not rust or react with other chemicals. Naturally a steel gray color and coming in a powdered form, tungsten carbide can be molded and shaped through extreme heat and pressure into a variety of shapes and forms.

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A gray, inorganic material, tungsten carbide functions as a hardener in armor-piercing projectiles, the sharp edges of drills and saws, and cast iron. Besides industrial uses, it is also used to create jewelry due to its hardness and deduced risk of allergic reactions among those with sensitive skin, among other desirable properties.

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Tungsten carbide is a common term used when discussing jewelry. However, tungsten carbide is used in a wide range of manufacturing processes. In many cases, tungsten carbide contains cobalt. Cobalt contains nickel and chromium. According to the New Jersey government website, these chemicals can increases the chances of severe asthma and "hard metal lung" disease. The average employee working with tungsten carbide does not have access to the testing equipment necessary to test for cobalt. However, thanks to government regulations, there is one way you can determine of the tungsten carbide you work with has cobalt in it.

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Carbide is a compound that is formed from carbon and another metal, typically tungsten, although there are many types of carbides, all with slightly different properties. Carbide is noted for its strength and durability and is often used in parts for tools. Because it is designed for durability, carbide has some fairly unique characteristics and determining if an item is made from carbide is not very difficult. Learning to distinguish carbide from other materials can be a valuable skill, as recycling carbide is fairly profitable.

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