A few years ago, we shared a blog about the 10 Futuristic Materials That Will Be Disrupting Product Design. Back then, we looked at the option of transparent aluminium, and it seems that this is now more and more prevalent in the real world.

Our team were not the first ones to discuss the idea of see-through metals, far from it. Transparent aluminium was famously referenced in Star Trek back in 1980s. In one classic scene from Star Trek IV: The Voyage Home, Scotty attempted to trade sheets of plexiglass for the formula for transparent aluminium.

Classic Star Trek scenes are becoming reality more and more often these days, with Captain Kirk heading into space in real life earlier this month. William Shatner, who played the character for many years, took a ten minute trip 100 kilometres into space on the Blue Origin New Shephard vehicle. Star Trek fans rejoiced as the famous figure finally became a real life astronaut decades after playing one on TV.

That’s probably enough Star Trek talk from us, but instead we are looking into the reality of see-through metal and answering all your transparent aluminium questions.

What Is Transparent Aluminium?

Transparent aluminium is also referred to as aluminium oxynitride. It is a see-through ceramic of polycrystalline that is made from a structure of oxygen, nitrogen, and aluminium. This impressive material looks completely see-through and is incredibly strong. Transparent aluminium is four times as hard as fused silica glass, three times harder than steel, and a whopping 85% harder than sapphire.

Not only is transparent aluminium very tough, but it also has an extremely high melting point and can remain solid up to 1200 degrees Celsius. This means it can be used for products which need to withstand super high heats while also being see-through. Transparent aluminium is also resistant to damage caused by oxidation and radiation and offers good resistance to corrosion. 

Can Aluminium Really Be Transparent?

A lot of people who come across transparent aluminium are left wondering if it really is the same aluminium which we know so well. The true answer to that question is that it depends on how you want to define aluminium. Normal aluminium is in high abundance and used for loads of day-to-day applications. It has all the properties you would expect from metal, including being thermally and electrically conductive. Aluminium can be melted and moulded into any shape, which is why it is used for so many objects such as cans and foil.

Transparent aluminium does not come with all these same features as standard aluminium. The truth is, aluminium oxynitride isn’t really a metal at all because it is made from equal parts aluminium, nitrogen, and oxygen. The chemical formula for this is AION, and it has actually been around for decades. It is only in recent years that advances in this technology have meant that transparent aluminium has been able to be introduced in various applications.

How Is Aluminium Oxynitride Made?

Now we understand that transparent aluminium isn’t just aluminium which is see-through, but an entirely new material altogether, you might be wondering just how it is produced. The ceramic material is heated to extremely high temperatures and then undergoes a grinding process. After grinding it is polished heavily, and it is this polishing process that creates the transparency. The grinding and polishing stages in the production of this material work to improve the strength and impact resistance.

What Is It Used For?

Transparent aluminium might have come a long way in recent years, but it is still an extremely expensive material to produce. While it has potential to be used for many everyday products, such as electronic devices and packaging, the cost involved means it is not yet accessible to these manufacturers.

Currently, transparent aluminium is being used for a range of defence applications. Transparent amour, bulletproof glass alternatives and sensor windows are all examples of applications where this material is being utilised. For this industry, transparent aluminium brings many benefits. A laminated pain of aluminium oxynitride which is 1.6 inches thick can put a halt to a 50 calibre rifle round. This is a claim that 3.7-inch traditional bulletproof glass can’t make. Also, unlike glass, transparent aluminium is transparent to infrared waves, making it effective for use on heat seeking missiles and other infrared technologies.

Transparent aluminium is not yet readily available for commercial products for everyday use or industrial product designs like mobile phones, but it is in the process of being adapted for such use, and this also brings many potential benefits for other future products. We don’t think it will be too long before this innovative material is available to the masses, and it will bring with it a whole host of new product opportunities.