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Feature: 5 Exotic Materials

Ever since it was discovered that combining iron, chromium and carbon made a material that could be used to make almost anything, stainless steel has been king of construction. It’s strong, it’s malleable, its hardy—and that’s why it’s also used for making watches. What more could you ask than that? Well, apparently you can get watches made of other, more exotic materials as well. But why?

Titanium

Aside from precious metals like gold, originally chosen for its attractive colour and ease of working with primitive tools, watches are made from stainless steel. It makes perfect sense because it gets the job done and is nice and cheap. It also takes a finish well and holds it, unlike gold, can be precision machined and fights off corrosion from things like saltwater.

In fact, the advent of the water-resistant watch in the 1920s really drove forward the use of stainless steel thanks to its tool-like properties, soon overwhelming gold in its use and becoming the staple of watchmaking. There really seems to be no reason to deviate from it, yet here we have a watch made from something entirely different: titanium.

Originally named—by the person who discovered it, Reverend William Gregor—as gregorite, the discovery of titanium in 1791 actually occurred some thirty years before stainless steel was invented. Renamed three years later after the Greek Titans, it was abundantly clear from the start that titanium is a rather special element.

Problem was, they couldn’t actually get at it. It wasn’t until the invention of electricity that the process of extracting titanium from its ore could be achieved, thanks to the enormous temperatures and complicated chemical process required to achieve it. By 1910, a 99.9% pure titanium was finally realised, and the full potential of titanium became available.

And what amazing potential it had. It matches steel for strength yet weighs about half; it has a melting point close to 2,000 degrees Celsius; and it has incredible corrosion resistance, forming a natural skin that protects it from attack. All this sounds like the perfect recipe for things that go fast, get hot, and get put under huge strain, and that’s why the aerospace industry jumped on it.

It also makes titanium an excellent choice for a wristwatch, added to the nontoxic benefits that have seen titanium adopted by the medical industry as well—but logic never prevails because, for many people, the absence of mass that titanium affords can feel sort of … cheap. It’s why you don’t see titanium more often, despite its incredible properties. It’s just the way of the human brain, and there’s no figuring that out.

Ceramic

A few decades ago and the mention of ceramics would bring to mind a coffee mug or a plant pot. These are ceramics, but the material has come on a long way since humans first realised they could bake clay into a hard, brittle material some 27,000 years ago. The mid-20th century yielded the first prominent development in what’s now known as technical ceramics thanks to advances in technology—but before we go too far down this particular rabbit hole, it’s probably worth understanding what a ceramic actually is.

Perhaps you’d think a ceramic material would be defined by chemical composition, or molecular makeup or something sciency like that, but it’s not; it’s quite simply a non-metallic solid that’s been hardened at high temperature. That’s why advanced materials like zirconium dioxide and garden pot clay can be classified by the same name despite such disparity.

But don’t let the term ‘non-metallic’ mislead you. Zirconium is of course a metal, and here’s where woolly terms come into play again, because metallic simply means ‘like a metal’. So as long as the compound containing a metal ends up not very metal-like—for example, brittle, dull, a poor conductor—and requires heat to get there, it’s a ceramic.

So, what’s the point of technical ceramics? While there will be no call for them from Royal Doulton any time soon, this high-tech material offers a litany of uses: piezo-ceramics can convert electrical signals into movement and vice-versa; non-oxide ceramics, like the tungsten carbide used in cutting tools, exhibit high wear-resistance; and oxide ceramics, like the zirconium dioxide used in watchmaking, have incredibly high scratch-resistance.

You can immediately see the appeal of oxide ceramics in watchmaking. As any watch owner who’s misjudged a doorway or table edge will attest, scratch resistance is very desirable. Lab-grown sapphire has made crystal scratches virtually a thing of the past—sapphire is a ceramic, by the way—and zirconium dioxide can do the same for cases.

Two problems: the first is how difficult technical ceramics like zirconium dioxide are to make. Forming the stuff in the first place requires temperatures of over 1,500 degrees Celsius to bind the zirconium powder together, but it’s in the finishing that things get really hard. Literally, because zirconium dioxide is very, very hard—the diamond substitute cubic zirconia is only a slight shift in molecular structure away after all. Finishing a ceramic case is slow, intensive and costly.

The last issue with technical ceramics is one of practicality. Being a hard material, just like the clay pots and porcelain plates its related to, makes it brittle too. In the unlikely event that a ceramic case were to meet a sharp, forceful impact, it won’t dent, but rather chip or even shatter. Like the change from plastic to sapphire crystals, it’s the price to pay for the extreme scratch resistance.

Bronze

We go from the extremely high-tech to the literally bronze-age material that’s become du jour in watchmaking recently. Bronze hasn’t changed a whole lot in the last 4,000 years since the alloy was first stumbled upon—primarily because it’s just not used much anymore. Bronze was knocked off the top spot some 3,000 years ago when iron was discovered, and then later iron’s alloy, steel.

Bronze is not as hard as steel. It’s not as light as titanium. It’s abundant, but not as much so as iron. It’s an all-round loser—yet somehow, it’s made a bit of a comeback. This is true in two senses: bronze, originally an alloy of copper and arsenic, then—thanks to arsenic’s less-than-ideal health properties—an alloy of copper and tin, has been given a bit of a makeover for the modern world.

Scientists threw in some aluminium, nickel, iron and manganese and ended up with a variant of bronze that has become the mainstay of the modern marine industry. Like titanium, bronze forms a skin of oxidisation that resists not only corrosion, but the growth of marine life as well, perfect for keeping propellers and the like clean, balanced and efficient.

And it’s that skin that’s brought bronze into watchmaking. A material suited to underwater use obviously has its benefits in a dive watch, but there’s never been an underwater expedition long enough for the growth of marine life on its participants to ever be an issue—so why use it over steel?

Once again, mind prevails over matter. Like titanium, the practical benefits of bronze take a bit of a back seat, because it’s how that skin looks that makes bronze so appealing. It forms in a random way, darkening the once bright and shiny case into a dull, mottled pattern that’s completely unique. There’s something distinctly nautical about the way it ages, the way touch points remain polished—there’s a reason its most common usage is in the production of art.

How much a watch benefits from bronze’s marine capabilities over steel is questionable, but as we repeatedly point out, a watch is about more than simply practicality. Bronze ages with you, matures, offers a new experience every single day. It tickles the nostalgic part of the brain that thinks back to the early days of diving and the risks those people took to discover a new world. Can steel do all that?

Carbon Fibre

Modern technology has done a lot for material science, and for carbon in particular. It’s a very versatile element, making up everything from diamond to the skin you’re wearing right now. As the sixth most abundant material in the universe, carbon is the very backbone of life as we know it, and conversely has the power to destroy everything—for watches, however, it’s not so common.

Carbon found its way into industry as the rods in the first electric streetlamps in the 1800s, fitted in pairs and charged with electricity, the arc jumping between the tips and emitting light. The rods shrank to filaments for Edison’s incandescent light bulb towards the end of the century, and the filaments briefly became ropes at the end of World War II.

But there was a better use for these thin strands of carbon when taken to the extreme: by vaporising carbon under extremely high pressures and temperatures, physicist Roger Bacon discovered that the molten lump that emerged could be broken apart into strands a tenth the thickness of a human hair, but with strength ten times that of steel and a weight one-fifth. Only problem was that it cost about $20,000 to make just one gram.

The promise was so great that it only took a year to refine the process and bring the cost down. By the early sixties, carbon fibre was a commercially available product, and thanks to its light weight and high strength, was quickly adopted by the aviation industry. By using woven matts of carbon fibre formed in moulds, saturated in resin and cured with heat, the material introduced a way to form complex shapes that were structurally rigid without the volume and thickness typically required for steel. It was a revelation.

Its use not only in aviation, but also in motorsport, makes carbon fibre the ideal candidate for manufacturing a wristwatch with. Well, in theory, because actually making things out of carbon fibre is pretty tricky. A steel case can be stamped in one piece, milled by machine and finished by hand—every carbon fibre component must be built in layers from sheets a tenth of a millimetre thick, impregnated with resin and cured in a vacuum. It’s a long, arduous process, and is part of the reason why carbon fibre watches are so scarce.

But carbon filament technology hasn’t stopped there; scientists are currently experimenting with carbon nanotubes. These are filaments rolled from graphene, sheets made of a single layer of carbon atoms. With graphene some sixteen times thinner than human DNA, and the nanotube structure some forty times stronger than carbon fibre, carbon nanotubes are mooted to be the material of the future. And believe it or not, but carbon nanotubes can already be found in a few concept watches: in the 360,000 vph balance spring of the Zenith Defy El Primero 21 and as blacker-than-black Vantablack in the H. Moser & Cie. Endeavour Perpetual Moon Concept Vantablack.

Forged Carbon Fibre

If you’re aware of Lamborghini’s ridiculous Huracán Performante, the Italian supercar-maker’s even crazier version of the already bonkers Huracán, perhaps you’ll be aware of forged carbon fibre. Where most cars like the Huracán might be tricked out with the immediately recognisable weave of carbon fibre, the Performante has glossy black parts that look a bit like they’ve been wiped with a dirty rag. This is forged carbon fibre.

Lamborghini introduced forged carbon fibre to the world in the shape of the 2010, $3m Sesto Elemento, a stripped-out concept car that made abundant use of the sixth element on the periodic table—that’s sesto elemento if you’re Italian—carbon. It had amongst other bits, a carbon chassis, a carbon fibre drive shaft and carbon fibre suspension, bringing weight down to less than a Nissan Micra.

But the astonishing light weight and subsequent 2.5-second sprint to 60mph were overshadowed by the type of carbon fibre that Lamborghini used, however, a weird, marble-like concoction that looks almost organic called forged carbon fibre. With some 500,000 shredded strands of carbon fibre per square inch, the loose mix of chopped material forms a more complex structure—known as a non-directional matrix—than the ordered weave of traditional carbon fibre, with the swirly pattern as a by-product.

This unique approach to carbon fibre seems like one that would be right at home with watchmaking—and funnily enough, it already is. How soon did a watchmaker feature this material after it was debuted by Lamborghini in 2010? Well, three years earlier, actually. The 2007 Audemars Piguet Royal Oak Offshore Alinghi Team Chronograph debuted forged carbon fibre to watchmaking, and the brand continues to use the stuff in its flagship models today.

Many other brands making carbon fibre watches outsource to industry suppliers to help them with such tricky and limited pieces, but not Audemars Piguet. When then-CEO Georges-Henri Meylan discovered the lightweight technology at an aerospace trade fair, he knew he was on to something special, and rather than take the easy route and outsource the work, he hired a specialist from the industry to develop the capability in-house instead. Carbon fibre strands are hand cut and forged under pressure and heat to create the unique pattern found in every watch. It’s laborious and painstaking, but then it does also make the watch look like a Lamborghini.

It seems that steel will continue to be the go-to material for making watches, and it really does make sense. But the interesting, the exotic, the unusual, they have a place too—not just from the point of view of development and experimentation, but for the emotive experience as well. Owning a timepiece made of something unique, that develops a pattern that will only ever happen once, or that has been formed through an extensive and high-tech process rarely seen outside of the forefront of science is a pleasure all in itself.

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