Materials of the Future
It’s better to implement ideas than to simply dream of them. And that’s exactly how the developers of
At first glance, innovation may not be apparent. Philipp Kellner has placed a pressed sheet steel component on the table. It will later be affixed to the vehicle’s sill, accommodate the door hinges, and enclose the front windshield on its vertical side, as explained by the
The invisible backbone
Black plastic with rhomboid struts encases the high-strength metal and braces it from the inside. “What you don’t see here,” Kellner elaborates, “are the two additional layers of thermoplastic glass-fiber plastic panels between the liquid-injected, short glass fiber-reinforced plastic and the metal. We call them organic sheet composites.” Taken together, the result is the 3-D Hybrid A-pillar, a novel type of hybrid design invented by
The basis of this research can be seen by any driver of the 918 Spyder and the current
In questions concerning the selection of material and possible production methods, the development experts are supported by their collegues in the Material Technology department under the leadership of Stephan Schmitt. Unconventional thought is a prerequisite in that process. For example, most smartphones utilize Gorilla Glass, a high-strength, thin glass with perfect optical properties. “For the first time in the 918 Spyder with the Weissach package, we used a small window of a similar material: a laminated glass pane made up of two thin glass sheets with a film between them.” Markus Schulzki from the Structure Predevelopment department holds a glass pane that’s roughly twenty centimeters square: the rear window between the roll bars behind the seats of the sportiest 918. It’s surprisingly light. If one taps it, it sounds like plastic. “That’s what everyone thinks,” says Schulzki. “But it’s glass. This here was a practice run. Today we’re far beyond that stage.” In the current
Glass revolution in the interior
With the smartphone, the communication technology of the automotive industry has delivered a material that can also be used as a carrier of information in the vehicle. In addition to exterior components, Mathias Fröschle and team also develop interior solutions. His vision: “A center console whose sweeping surface is entirely made of thin-sheet glass. Thanks to the film, you can create displays and control elements as precisely as the driver and passenger need them. Gesture control is used to activate the menu, and confirmation that a command has been executed is received via haptic feedback through contacts in the glass.”
Hendrik Sebastian and his colleagues can imagine other uses as well: “Completely new forms, discs, and displays with augmented reality display features. The passengers see an old castle through the window, tap the glass surface, a side camera captures the castle, compares the image with information from the Internet, and delivers it in real time on the window next to the actual castle.” The film between the glass layers functions as a screen—this is no figment of the imagination, but the current state of research. Graduated darkening of the windows depending on the intensity of sunlight or passenger preferences is also possible.
Porsches made of plants
Additive manufacturing is the method popularly known as 3-D printing and the specialty of Falk Heilfort and Frank Ickinger from the Powertrain Predevelopment department, who present a cylindrical component for consideration. It’s the rotor shaft of an electric motor, and is responsible for transferring the electromagnetically generated torque to the gearing—the crankshaft of an electric motor, so to speak. “This rotor shaft consists of a special stainless steel,” explains Heilfort. Next to the shaft there’s a tiny glass pipe with a gray, fine powder: the microscopically fine-grained base material of the solid component. In a clean room, this powder is spread in a thin layer on a surface and then melted with a laser to form a firm bond, after which the next layer of powder is applied and once again melted with the laser. Layer by layer. Thus emerges a roughly fifty-centimeter-long rotor shaft out of the powder. The advantage over a conventionally milled and turned component: much less material is used, the excess powder can immediately be put to use, and it enables more complex forms. The rotor shaft thus has fine ribbing on the interior, which lends greater strength.
It wouldn’t be possible to produce such shapes on a lathe. It would be necessary to first cast the shaft and then weld it to get the same result. “This component is much stronger, much lighter, more rigid, and delivers much better power transmission,” says Ickinger, rattling off the benefits. The disadvantage so far: “It still takes about thirteen hours to print such a rotor.” Series production is therefore not yet planned; and yet, this technology will one day revolutionize powertrains. Hendrik Sebastian adds, “Additive manufacturing is revolutionizing the way in which we develop components. We can optimize and test much more rapidly and also significantly enhance performance. It’s an outstanding product and process innovation whose potential is far from exhausted. Many challenges are yet to be mastered, but we wouldn’t be
While there will not yet be a renewable
By Thorsten Elbrigmann
Photos by Rafael Krötz