Many of today's mid-range, high end and flagship grade smartphones have that some reviewers call a premium build quality and finish, built out of aluminium. This is technically incorrect, as smartphones are built out of an aluminium alloy, and there are various grades available - different grades consist of different source materials and blends, with different strengths and other mechanical properties. For 2015, Samsung finally realized that they, too, could build a smartphone that did not have a plastic shell - although for some time, Samsung have been using what sound like exotic alloys as part of the chassis of the smartphone. And so the Galaxy S6 arrived, a blend of aluminum alloy and glass. The latest rumors are suggesting that for the next iteration of the Samsung Galaxy S flagship series, Samsung will switch to a magnesium alloy.
Magnesium alloys have been used for mobile and portable computers for some time now and it's easy to understand why. For comparable mechanical strengths, magnesium alloys are around one third less dense, or in effect lighter. To take one example, the Galaxy S6 is built of 6013-grade aluminum alloy. 6013-grade aluminum has a density of 2.71 g/cm3, whereas many magnesium alloys have a density of around 1.8 g/cm3. This means that a chassis and shell built from magnesium alloy will weigh two third as much as the equivalent thickness and construction of an aluminum shell. In turn, this means that the overall device is lighter, or could be built to the same thickness and be stronger and more resilient. In other respects, magnesium alloys are at least comparable to aluminum alloys, being just as effective at conducting heat away (this could be relevant in an era of heat pipe cooled devices), but are less blocking of radio signals. Magnesium alloys also have a lower melting point and the material is somewhat easier to machine and otherwise work with which makes up for the fact that the raw material is more expensive than aluminum: the end product is similarly priced.
Will Samsung release a magnesium-shelled Galaxy S7 device? We don't know, but the material is certainly suitable and has already been seen in a number of other devices such as the OnePlus Two and the Oppo R1. A magnesium alloy-based Galaxy S7 might sound amazing, but let's wait and see what else Samsung do with the device, such as software improvements.