Samsung's Galaxy line of smartphones is, without a doubt, a smash hit, but one of the few complaints relates to the plastic casing.

Various rumors suggested that the new flagship may finally break that plastic habit and boast a more stylish metal body, but the Samsung Galaxy S4 came out and it's still polycarbonate.

As one would expect, hopes don't die that easily and now attention turns toward the next iteration, purportedly the Samsung Galaxy S5, to carry that metal torch. The sequel to the wildly popular Samsung Galaxy S4 may be the first smartphone in the Galaxy line to sport an aluminum body.

Considering that the Samsung Galaxy S4 sold a whopping 40 million units in just one month after hitting commercial availability, imagine what records Samsung could smash if it raised the stakes a bit and go for top-quality materials. According to a new report from Android Geeks, Samsung may finally step it up a bit with its next-generation flagship.

The publication notes that the Samsung Galaxy S5 will benefit from the company's "new design direction" reportedly called "Design 3.0."

"As you've probably noticed, the other big players of the smartphone world are trying to make their terminals look as premium as possible (see HTC One and Sony Xperia Z) using materials like aluminium or glass for their cases," Android Geeks notes. "In an attempt to find out whether Samsung is ready to fight back at its rivals with premium-looking Samsung Galaxy S5, we stretched out antennas and managed to find out that the successor of the Samsung Galaxy S4 will have an aluminium body. The information was provided to us by a trusted source close to the South Korean phone maker, who wanted to remain anonymous."

"While we don't have the slightest idea what Design 3.0 really means in terms of looks, we can now confirm that Samsung will start to use aluminium for its high-end smartphones, and the Samsung Galaxy S5 will be the first one to receive this treatment."

An aluminum body would come as a major improvement and would most likely boost the Samsung Galaxy S5's popularity to tremendous dimensions. On the other hand, as Android Geeks accurately points out, metal bodies do come with some expenses. Smartphone makers seem to favor the unibody construction, and a unibody casing means non-removable battery. Second, metal smartphones take longer to manufacture. A company must take into account yield rates, i.e. how quickly and efficiently it can make the device and have it ready to ship a high volume of units.

Considering that the Samsung Galaxy S flagships are growing increasingly popular with each generation, the Samsung Galaxy S5 is expected to surpass the popularity of its predecessor. That would mean a stellar demand for the next-generation Galaxy flagship, and lower yield rates associated with aluminum constructions might mean stock shortages.

The Samsung Galaxy S4, however, is just fresh out the market, which means there's still nearly a year until the next iteration is ready to make its debut. Samsung has plenty of time to work out the fundamentals and a lot could change until then.