In a recent roundtable discussion with Frank Ickinger (Senior Engineer Advance Engineering at Porsche AG), we had the opportunity to learn more about Porsche’s 3D-printed pistons for the Porsche 911 GT2 RS. Yes, metal alloys can be 3D-printed now.
Although the technology application is for small series productions, it does create new business opportunities for Porsche. Three innovation clusters emerge with it.
The 3D printing technology is the joint work of Porsche AG, Mahle GmbH, and Trumpf. The 3D printed pistons are made of aluminium powder from a special alloy developed by Mahle. Trumpf is specialises in laser technology. The aluminium powder is printed using laser metal fusion process.
It takes 12 hours to print 5 pistons and the process is very costly. In return, the 3D-printed pistons are 10% lighter, 20°C cooler, and stiffer than their forged counterpart. With 3D printing, the shape of the piston can be more ‘bionic’, allowing added reinforcement where needed.
The 3D-printing effort is Porsche pushing the boundaries of technology. Its is expensive and not economical.
The biggest challenge in the development of the pistons was the durability. In terms of surface smoothness, the 3D-printed pistons (after machining and sand blasting) are closer to casted pistons than forged pistons.
Thanks to the 3D-printed pistons, engine speed can be increased, the temperature load on the pistons can be lowered, combustion can be optimised, efficiency is improved, and 30 PS more power can be extracted.
With the flexibility of 3D printing, replacement parts for classic Porsche models (e.g. clutch release lever for Porsche 959) can also be recreated without the need for extensive tooling.