Apple wants to make its next Apple Watch out of something harder, lighter, and more scratch-resistant than the aluminum alloys it’s used for a decade. The material is called bulk metallic glass, and a recently published patent application suggests the company is serious about deploying it in future wearables. But here’s the thing: bulk metallic glass has been a “next big material” for consumer electronics for over 15 years. The gap between a patent filing and a shipping product is enormous — and Apple knows that better than anyone.
The patent, first spotted and reported by Digital Trends, describes an aluminum-based bulk metallic glass (BMG) alloy specifically designed for wearable device enclosures. The filing details compositions that include aluminum combined with elements like nickel, cerium, and lanthanum in precise ratios. What makes BMG different from conventional metals is its atomic structure. Traditional aluminum is crystalline — atoms arranged in an orderly, repeating lattice. BMG is amorphous, meaning atoms are arranged more like a liquid frozen in place. That disordered structure gives it unusual properties: higher strength-to-weight ratios, better corrosion resistance, and superior elasticity compared to standard aluminum alloys.
On paper, it sounds ideal for a smartwatch case. And Apple’s patent language makes it clear the company is thinking about exactly that application.
But patents aren’t products. Apple files thousands of patents every year, and the vast majority never see the inside of a retail box. The company has, in fact, been filing BMG-related patents since at least 2010, when it acquired Liquidmetal Technologies’ intellectual property rights for consumer electronics applications. That deal gave Apple exclusive access to Liquidmetal’s amorphous metal alloy formulations. Fourteen years later, the most prominent use of that technology in a shipping Apple product has been… the SIM card ejector tool that came with some iPhones.
Not exactly a flagship deployment.
The Manufacturing Problem Nobody Wants to Talk About
The reason BMG hasn’t shown up in Apple Watch cases yet isn’t a mystery. It’s manufacturing. Bulk metallic glass must be cooled extremely rapidly during production — on the order of thousands of degrees per second — to prevent atoms from organizing into a crystalline structure. This limits the size and thickness of parts you can reliably produce. For a tiny SIM tool, that’s trivial. For a watch case with complex geometry, antenna windows, sensor cutouts, and tight dimensional tolerances? That’s a different problem entirely.
Researchers have been chipping away at this constraint for years. A 2020 study published in Nature Communications demonstrated progress in producing larger BMG components, but the techniques involved — like thermoplastic forming and additive manufacturing — still don’t operate at the volumes or costs Apple requires. Apple ships roughly 50 million Apple Watches per year, according to estimates from Counterpoint Research. Producing that many BMG cases with current technology would be economically impractical.
So why file the patent now? Likely because Apple’s materials science team has made incremental progress on aluminum-based BMG formulations that cool more easily than zirconium-based alternatives. The patent specifically references aluminum-nickel-cerium compositions, which academic literature suggests have somewhat more forgiving cooling requirements. But “more forgiving” is relative. We’re still talking about a material that demands specialized casting equipment and process controls far beyond what conventional CNC machining of 7000-series aluminum requires.
There’s also the question of repairability and recycling. Apple has made loud public commitments to using recycled materials in its products. The company’s 2024 environmental report states it now uses 100% recycled aluminum in several product lines. BMG alloys, with their exotic elemental compositions including rare earth elements like cerium and lanthanum, don’t fit neatly into existing recycling streams. That’s not a dealbreaker, but it’s a real tension Apple would need to resolve before shipping BMG at scale.
And then there’s cost. The current Apple Watch SE starts at $249 with an aluminum case. The standard Apple Watch Series 9 starts at $399. Apple already offers titanium cases in the Ultra line starting at $799. Where would a BMG model sit in that lineup? If manufacturing costs push the price above titanium, the value proposition gets murky fast. BMG is harder than standard aluminum, yes, but titanium already offers excellent scratch resistance and a premium feel. Consumers would need a compelling reason to pay more.
None of this means Apple won’t eventually ship a BMG Apple Watch. The company has a long track record of investing in materials science years before deployment. It spent the better part of a decade perfecting its ceramic Apple Watch cases before quietly discontinuing them. It developed custom titanium machining processes for the Ultra. Apple thinks in long arcs.
But industry insiders should be clear-eyed about the timeline. The patent describes research-stage work, not production-ready engineering. No credible supply chain reporting — not from Bloomberg, not from Ming-Chi Kuo’s supply chain analysis — has indicated BMG components are entering Apple’s procurement pipeline for near-term products. The earliest realistic window, assuming Apple solves the manufacturing and cost challenges, is likely 2027 or later. And that’s optimistic.
What the patent does confirm is that Apple hasn’t abandoned its Liquidmetal investment. The company is still actively researching amorphous metals, still refining compositions, still exploring applications. That’s meaningful. It suggests internal confidence that the manufacturing barriers will eventually fall. But “eventually” is doing a lot of heavy lifting in that sentence.
For now, the Apple Watch will continue shipping in aluminum, stainless steel, and titanium. These are proven materials with established supply chains, well-understood recycling pathways, and costs that fit Apple’s margin targets. They work. BMG might work better someday. But someday isn’t this year, and it probably isn’t next year either.
The honest read: Apple’s BMG patent is a sign of genuine long-term materials research, not an imminent product announcement. Treat it accordingly.
WebProNews is an iEntry Publication