Porsche develops new application for 3D printing together with Mahle and Trumpf

The piston blanks after the printing process

Innovative pistons from a 3D printer for increased power and efficiency

3D printing technology is already used at Porsche in prototype construction, manufacturing spare parts for classic sports cars as well as in other areas. In cooperation with its partners Mahle and Trumpf, the sports car manufacturer is now establishing a new milestone in the use of additive manufacturing processes for highly-stressed drive components. For the first time, the pistons for the high-performance engine of the 911 flagship model, the Porsche 911 GT2 RS, are now also being produced with a 3D printer.

The pistons are printed layer by layer using a laser .

3D printing benefits

3D printing allows the pistons to be manufactured with a structure that is optimised for the loads acting on the pistons. As a result, the pistons from the advance development project weigh ten percent less than the forged series production pistons. They also have an integrated and closed cooling duct in the piston crown that could not have been produced by conventional methods. “Thanks to the new, lighter pistons, we can increase the engine speed, lower the temperature load on the pistons and optimise combustion,” explains Frank Ickinger from the advance drive development department at Porsche. “This makes it possible to get up to 30 PS more power from the 700 PS biturbo engine, while at the same time improving efficiency.”

The pistons are printed layer by layer using a laser

Building up parts layer by layer permits realisation of new and improved designs

There are a number of different technologies for 3D printing. All are based on the principle that the components are built up layer by layer without the need to previously manufacture a special tool or mould. Practically any geometric shape can therefore be realised. The printer can be fed with the design data directly from the computer.

Pistons for the 911 GT2 RS from a 3D printer (right) in comparison to the production piston (left)
Pistons for the 911 GT2 RS from a 3D printer (right) in comparison to the production piston (left)

Additive manufacturing processes are thus ideal for producing structures that have been designed and optimised by means of artificial intelligence (AI). The pistons of the Porsche 911 GT2 RS were manufactured from high-purity metal powder using the laser metal fusion process (LMF). Here, a laser beam heats and melts the powder surface corresponding to the part contour. Porsche initiated the joint project together with cooperation partners Mahle and Trumpf. The quality and performance capability of the components were validated using measurement technology from project partner Zeiss.

Wide application field and new potential uses for 3D printing at Porsche

The pistons are subjected to the toughest tests on the engine test bench in a 911 GT2 RS engine
The pistons are subjected to the toughest tests on the engine test bench in a 911 GT2 RS engine

Porsche already uses additive manufacturing processes in several areas. For example, a 3D-printed bodyform full bucket seat has been available since May for the model series 911 and 718. Here, the central section of the seat, in other words the cushion and backrest surfaces, is partly produced by a 3D printer. Customers will be able to choose between three firmness levels (hard, medium, soft) for the comfort layer in future. Porsche Classic also uses additive processes to reproduce plastic, steel and alloy spare parts that were previously no longer available.

After the test runs, the pistons are removed for analysis

A release lever for the clutch of the Porsche 959, for example, today comes from a 3D printer. Around 20 reproduced parts for Porsche classic models are currently manufactured using additive processes. This manufacturing technology is also technically and economically interesting for Porsche for special and small series as well as motorsports. 3D printing therefore offers significant potential for Porsche with regard to product and process innovations, which will in turn allow customers to benefit from fascinating and individual products.

Edited Porsche factory press release.
Pictures courtesy Porsche AG