In cooperation with Porsche and Trumpf, Mahle has produced high-performance aluminium pistons using 3D printing techniques for the first time.
The 3D-printed aluminium pistons were successfully tested on the engine test bench for Porsche’s 911 GT2 RS sports car. “The results of the project confirm the great potential of 3D printing and demonstrate Mahle’s particular competence in the field of high-performance small and limited runs and in relation to prototyping and aftermarket,” says Martin Berger, head of Corporate Research and Advanced Engineering at Mahle.
The new process presents the option of implementing a so-called bionic design. In this approach, which mimics natural structures, material is added only in loaded areas, with the structure of the piston being adapted to the load. It saves material and has the potential to make the 3D-printed piston up to 20 % lighter than its conventionally manufactured counterpart while increasing rigidity.
Special aluminium alloy for pistons also suitable for 3D printing
The new production process is based on a special aluminium alloy developed by Mahle with a long history of successful use in cast pistons. The alloy is atomized into a fine powder and then printed in a process known as laser metal fusion. A laser beam melts the powder to the desired layer thickness, followed by the application of a new layer on top, thereby building the piston up one layer at a time. Using this method, 3D printing specialist Trumpf produces piston blanks made up of approximately 1,200 layers in around 12 hours.
The piston blank is then finished, measured, and tested at Mahle and must meet the same strict standards as a conventionally manufactured part.
Mahle is set to harness the potential of new production processes, such as 3D printing, for further projects and aims to expand its competence in this area specifically.