SlashGear’s Chris Burns cited an anonymous source this week claiming to have seen Liquidmetal technology being used in an Apple device much larger than an iPhone, and says that while a vague tip (anonymous to boot), wouldn’t normally be something he’d cover, “… the possibility that this could be the next big MacBook Pro feature is just too perfect not to consider.”
Last week, the Korean journal ETNews’s Kim In-soon reported that the next iPhone will swap the iPhone 4 series’ glass case material for Liquidmetal alloy, which was developed by a California Institute of Technology research team that later organized themselves into the Liquidmetal Technologies firm. Apple paid $20 million for licensing rights to Liquidmetal Technologies’ “amorphous metal alloys“ in 2010.
Despite the name, Liquidmetal alloys are not liquid, but solid at room temperature, and are claimed to be hard-wearing and able to withstand thermal cycling, along with a constellation of other desirable material features—including high tensile strength, excellent corrosion resistance, very high coefficient of restitution, and excellent anti-wearing characteristics—while being able to be heat-formed in processes similar to thermoplastics.
The Liquidmetal company describes its technology thus:
Liquidmetal alloys are a revolutionary class of materials that redefine performance, process, and design paradigms. Liquidmetal alloys represent the first enabling materials technology since the creation of thermoplastics and possess characteristics that make them superior in many ways to other popular high performance materials. First, they have an “amorphous” atomic structure, which is unprecedented for bulk structural metals. Second, they include a multi-component chemical compositions, which are optimized for various properties and processes. Finally, our metal alloys are the first commercially available metals with process technologies similar to plastics.
Wikipedia has a somewhat more detailed explanation of Liquidmetal alloys’ properties noting that they contain atoms of significantly different sizes that form a dense mix with low free volume, and unlike crystalline metals, there is no obvious melting point at which viscosity drops suddenly. Rather they behave more like glass, in that viscosity drops gradually with increased temperature, and at high temperatures it behaves in a plastic manner, allowing mechanical properties to be controlled relatively easily during casting.
Because these alloys have relatively low softening temperatures (400°C / 752°F for the earliest formulation), they can be molded, and allow casting of complicated shapes without need of finishing with material properties immediately after casting being much better than when casting with conventional metals, which usually need a lot of post-casting finish work. They also have low shrinkage during cooling.
While a switch to Liquidmetal from the current glass back enclosures rumored to be coming with the sixth-generation iPhone, likely next fall, seems plausible, a parallel move for MacBook laptops this year doesn’t. However, parallels with Apple’s interest in and development of aluminum “unibody” technology seem obvious, and if Liquidmetal iPhone enclosures prove successful, it would seem likely the material and technique will be expanded for use with other Apple products as well, perhaps displacing the expensive and demanding process of machining device housings from a single billet of aluminum altogether. Casting should be significantly cheaper and faster than machining for volume production, and with Liquidmetal’s other desirable qualities, the upside for both Apple and for end-users could be substantial.