What is Tantalum?
It is a hard, blue-grey, lustrous metal. Raw Tantalum rarely occurs in nature. Instead, it is typically found in the ore columbite-tantalite (commonly referred to as Coltan). This material is often produced alongside the material Niobium, which has similar chemical properties and tends to be found in the same regional mineral deposits as Tantalum. Early on, when the two metals were discovered, they were thought to be the same element due to their similar chemical and physical characteristics.
It is considered a relatively rare element. As it is scarce and offers desirable chemical properties, it is often used in formats that save material while maximising impact, such as coatings, wires and powders etc.
This material has multiple unique properties which have led to its increased and efficient use in the 21st century. It is highly corrosion resistant in air and moisture, due to the presence of an oxide film on its surface. It is also a highly stable metal that is almost immune to attack or degradation by acids and other chemicals at temperatures lower than 302 °F (159 °C).
Like many metals, it forms a thin but dense protective oxide layer when exposed to the atmosphere. This layer adheres to the surface of the metal, acting as a resilient barrier which protects the underlying metal from any further corrosion. Tantalum is a good conductor of heat and electricity and is among a group of metals known as ‘refractory metals’, which are defined by a strong resistance to heat and wear. It has a very high melting point of roughly 3017 °C, making it a metal with one of the highest melting points.
Is Tantalum flammable?
As a bulk metal, Tantalum is not flammable. However, in the form of a powder, it must be handled carefully and stored and transported in airtight containers. This is because dry Tantalum powder or very small granules may spontaneously ignite on contact with air, so must not be placed near open flames, sparks or smoke. In this format, the material is considered flammable, especially when exposed close to an ignition source.
Owed to its properties, Tantalum plays a vital role in several industries, such as modern electronics, the biomedical field, alloys and the aerospace industry.
It is now considered a technology-critical element. This is because, in the 21st century, it has become a crucial material for the electronics industry, with over 75% of electronics and components – such as mobile phones, computers, DVD players and video game systems – containing Tantalum in some format. In fact, roughly half of the Tantalum produced globally is now used in electronic devices, particularly in electrolytic capacitors.
With an extremely high melting temperature, it is a valuable ingredient in superalloys. These are high-performance mixtures of metals which are designed to withstand the extreme temperatures experienced inside of jet engines. These superalloys are critical to modern aircraft engines, and by using them, engines can operate at higher temperatures with improved fuel efficiency. Tantalum has also been used in alloys and carbides for space vehicles and supersonic aircrafts, particularly in parts such as turbine blades, rocket nozzles and nose caps, which need to maintain their structural strength at high temperatures.
Tantalum in Art and Design
One of the more decorative applications of Tantalum is in jewellery and luxury watches.
Since the metal is strong, beautiful, biocompatible and hypoallergenic, designers and brands are using Tantalum to create contemporary metal wedding bands. With its richly saturated yet natural blue-grey colour, rings made with Tantalum are able to compete with gold and platinum counterparts. The material is also applied extensively in luxury watches and dive watches, where it is used in tandem with other high-end metals, such as Gold and Titanium, not only to create a unique blended aesthetic, but also to ensure strength and corrosion resistance. Tantalum offers a unique dark blue or graphite pencil-like aesthetic here.
In other realms, Tantalum is able to increase the transparency and refractive index of glass. This can be valuable for lighting designers, artists and architects alike. These features and capabilities when lent to glass also translate to camera lenses, and therefore lenses made with the help of Tantalum Oxide containing glass are sought after by photographers.