Tungsten is almost a science fiction metal. Due to its unique properties, it is used in groundbreaking applications in high-tech industries. But why is a high density or high melting point so important? In this article, we discuss the various reasons why Tungsten is used in demanding markets and how it works in practice. Tungsten is not always easy to process. Metel advises or even takes over the manufacturing of Tungsten parts. Tungsten is the name of the chemical element with the symbol W and atomic number 74. In English, the element is called “Tungsten” due to a Swedish chemist who created a new foam from tung sten, meaning ‘heavy stone.’ The foam (Rahm) was referred to in German as comcombined with Wolf as the foam seemed to consume Tin during the process. The mineral Wolframite derived its name from this phenomenon. It was two Spaniards who first successfully isolated Tungsten by reducing the acid with charcoal, giving it the name Tungsten. Tungsten rings for two different high-tech applications

Tungsten Applications and Markets

Tungsten has two very remarkable properties; it boasts the highest melting and boiling points of all metals (3,410˚C and 5,930˚C, respectively) and a density comparable to Uranium and Gold, 1.7 times that of Lead. This leads to a significant amount of demaapplications of this high-performance metal, perhaps the most notable one being the filament of a light bulb. Here, it’s naturally the high melting point that makes Tungsten so suitable. But there are more interesting applications: Tungsten as a balancing weight – Metel supplies tungsten to a customer who manufactures machines for plasma separation, where Tungsten serves as a balancing weight. The same applies to the use of Tungsten in, for example, a car’s crankshaft. Tungsten enables more compact constructions – Engineers can design more compact systems simply because its specific gravity is higher. In the aforementioned plasma separation application, this means that the balancing weight takes up less space, allowing for more compact designs and innovations.iner construction. Tungsten for radiation shielding – Due to its high density, tungsten is exceptionally suitable for shielding against X-rays and is used in what was once known as a lead apron. Tungsten is non-toxic – Unlike lead, tungsten is non-toxic and can therefore be used in many more applications. Tungsten is highly heat-resistant under vacuum – The expansion coefficient of tungsten is low (4.5) compared to lead (29.3), making tungsten extremely shape-retentive and virtually indestructible. This is why it is frequently used in vacuum furnaces. This makes tungsten an essential material for the manufacture of high-tech components in industries such as aerospace, semiconductors, and energy.gie industry.

Processed Parts from Pure Tungsten

Working with pure Tungsten (min. 99.95% purity) can be challenging or require special tooling. As a result, Metel frequently supplies machined Tungsten parts to its clients, alongside other metals and alloys. “Our factory is equipped with all the knowledge and equipment necessary to process a wide range of alloys. An additional advantage is that any potential loss, for instance during machining, is immediately reused. This results in lower material costs.”

application-of-tungsten

Tungsten in Various Forms

In the image above, you can see copper-colored Tungsten (WCu80). This is one of the key alloys that Metel supplies to its clients. We would like to individually highlight three alloys:

Tungsten-Copper

In Tungsten-Copper alloys, the main consideration is the balance between wear resistance and thermal or electrical conductivity. Metel supplies Tungsten-Copper in a 70/30 ratio for the production of high-voltage conductors. We determine the correct composition in close consultation with the client.

Tungsten-Silver

This alloy has exceptionally good conductivity, better than Copper and even better than Gold. Tungsten-Silver is therefore used, for example, in welding electrodes. But the gebusing in ‘open’ air also has drawbacks, as Silver is very susceptible to oxidation. Due to oxidation, the conductivity of Tungsten-Silver in an application will relatively quickly deteriorate. Therefore, this alloy is mainly used when oxygen does not play a role. For example, in audio cables, Tungsten-Silver is used in combination with a good sheath that prevents the alloy from being exposed to air.

Tungsten-Nickel-Copper or Tungsten-Nickel-Iron Alloys

An alloy that offers the advantages of Tungsten but is not as challenging to work with as pure Tungsten is, for instance, the W95 or W97 alloy. The number refers to the percentage of Tungsten, with the remaining 3 percent consisting of Nickel combined with Iron or Copper. The choice is then determined byfor example, the desire for conductivity and the importance of a high specific gravity. The W97 alloy has a specific gravity of 18.5 g/cm3, and the W95 alloy has 17.6 g/cm3. In both cases, the alloy is easy to machine.

Alloys

Highly requested Tungsten alloys include:

  • W90NiFe/W90NiCu
  • 5NiFe/W92.5NiCu
  • W95NiFe/W95NiCu
  • W97NiFe
  • W90NiFeMo

Practical Example of Tungsten Application

In the image below, two rings are shown, the left ring is applied One of our customers uses the above-mentioned alloys in their refining application.depicted Tungsten ring (left). These rings are part of a carrier for copper components that are silver-plated in a chemical bath. Since the chemical bath through which the components move is electrically charged, it is crucial that the rings are somewhat conductive and corrosion-resistant. A Tungsten-Copper alloy is the best choice for this purpose. The left ring is made from the W90 alloy and proved to be too susceptible to wear. To reduce the wear of these components, we collaborated with this client to explore various Tungsten alloys. Pure Tungsten was found to be too expensive, and the W97 alloy was a step in the right direction. Ultimately, the choice was made for the W95NiCu alloy (3.5% Nickel, 1.5% Copper) as the most cost-effective solution.

The thicker ring is used in a high-tech electron microscope to bundle electrons into a straight beam.

Curious about the benefits of partnering with Metel? Our team is eager to share everything about our program and approach, and will gladly provide examples of successful collaborations with clients in your specific market. Schedule an appointment via 0416 – 724 800 or email n.kesteloo@metel.nl.