The process that's evolved over the years can be used to develop aluminum alloys, copper alloys, superalloys, and metal-matrix composites. It works by using nitrogen or argon gas to create a spray of molten metal that is precisely deposited on a rotating collector. This entire process happens within a chamber, so it's both highly controlled and safe. While this sounds incredibly simple, it's not. If it were, Osprey Metals probably wouldn't be able to license the process to companies like Germany's Peak Werkstoff GmbH, which supplies the Mercedes' cylinder liners.
Peak manufactures the cylinder liners from spray-formed billets by swaging the billets into tubes.
Of course, once the liners are cast into the block, they are turned and honed as would be expected. The key benefit of spray forming is that the rapid solidification of the sprayed droplets gives the resultant material a very fine and uniform grain. Compared to a cast iron liner, the spray formed aluminum-silicon one does cost more, however its use carries other advantages. Machining cost is also lower, as the substitution of aluminum for iron in the liners removes the need for mixed material machining on the top of the block where it mates with the cylinder head. A further bonus of the all-aluminum construction is easier recycling.