SlashGear reports that Apple could cast the chassis of the next MacBook Pro from Liquidmetal. But, just as with the iPhone 5 rumor, that this raises all sorts of issues related to whether this metal is transparent enough to radio frequency to allow Wi-Fi and Bluetooth to work properly.
A possible solution to this problem is offered up in the design of the Wi-Fi + 3G/4G iPad. The chassis of this product is machined out of aluminum, but in order to give the cellular antennas a window out to the world, there's a black plastic panel at the top of the tablet. It's not a particularly elegant solution, but I've never heard anyone complain about it.
But there's another possible obstacle to constructing a notebook chassis from Liquidmetal, and this one relates to how the material handles heat. The datasheet lists the thermal conductivity of the Liquidmetal as 6 Wm-1K-1, which makes it a far poorer conductor of heat than aluminum, which has a thermal conductivity of around 35 Wm-1K-1.
What this means is that Apple would need to redesign the cooling system of the MacBook Pro to take into account the fact that a Liquidmetal shell would be far poorer at dissipating the heat generated by the system than the current aluminum shell. However, buried on Liquidmetal Technologies website, a reference signals a way to tailor the material for specific thermal and electrical conductivity, so there may be possible to re-engineer the material to overcome this problem.
I like the idea of a Liquidmetal MacBook Pro -- or for that matter any portable -- more than I do the idea of making the back of an iPhone out of the material. The first reason is production. Casting is normally a much quicker process machining parts, and this gives the Liquidmetal chassis an advantage over how Apple currently manufactures parts for portable systems.
Another reason for switching from aluminum to Liquidmetal is that portables have to deal with countless bumps, scratches and abrasion on a daily basis. Liquidmetal would certainly offer a system far greater protection than aluminum does, and keep the hardware looking better for a lot longer.