Tungsten is the most refractory metal known to mankind.

It also has a very high density, one of the highest among metals, which in turn gives tungsten excellent radiation shielding properties.


Refractoriness and high density - these two main properties have determined its extreme importance in modern technologies and directions of its use.

But modern directions of science and technology sometimes require from refractory metals, and in particular, from tungsten, such a set of properties that tungsten in its pure form cannot provide. For example, it is often necessary to manufacture parts of a very complex shape.

Tungsten is a fairly brittle material under normal conditions, making it difficult to process. Another example is high electrical conductivity at high temperatures.

The electrical conductivity of tungsten does not match the electrical conductivity of copper, but at high temperatures, copper contacts simply cannot be used.

Therefore, in such cases, the so-called heavy alloys based on tungsten or simply tungsten alloys are used. Most often these are alloys of tungsten with nickel, iron, copper or with several metals at once. tungsten typically ranges from 90% to 98% by weight. In fact, these are not really alloys, but so-called pseudo-alloys.
at the melting point of tungsten, most metals are in the state of gases or volatile liquids. Therefore, pseudo-alloys are produced by powder metallurgy. Powders of pseudo-alloy components are mixed, pressed and sintered in the presence of a liquid phase of more low-melting metals and a solid tungsten phase.

Copper, nickel, and iron bind the tungsten grains to increase ductility, machinability and electrical conductivity.

Some applications of tungsten alloys:
The main areas of application for tungsten alloys are determined by their properties.

For example, one of the most important properties of tungsten alloys is high radiation protection, which is mainly determined by the high density of these alloys (tungsten alloys are more than 1.5 times heavier than lead).

Heavy tungsten alloys have been recognized as the best gamma ray shielding material compared to traditional lead, steel, cast iron and water. This property has led to the widespread use of VNZh and VNM alloys in the following areas:
Storage tanks for radioactive substances
Radioactive Logging Tool Parts
Non-destructive testing equipment
Dosimetry equipment and radiation control
Collimators, protective screens and other parts of various equipment
In addition, tungsten alloys are widely used for the manufacture of various kinds of weighting materials, electrical contacts, as well as components for the defense industry. In addition to tungsten pseudo-alloys, alloys based on molybdenum have also become widespread.