Why the Auto Industry is Following Tesla’s Lead into Large-Scale Castings

There are manufacturing benefits too, according to Began. “There is better modeling of performance and it really simplifies the supply chain,” he said. “There is just one piece for that whole weld assembly from a single source as opposed to numerous components, fastener nuts, and rivets coming from different places. You may go to a single supplier from dozens. A lot of those parts they may have been getting from overseas.”

“Megacasting is of utmost importance for the entire die-casting industry,” stated Cornel Mendler, Managing Director of Bühler Die Casting. “Megacasting gives the trend towards structural casting another push by extending the range of applications to complete body sections with the use of the new large Carat solutions with up to 92,000 kN locking force." 

Bühler's site states:

“Megacastings reduce complexity in production by enabling between 70 to 100 parts to be replaced by a single die-cast part. These single-piece castings will generally be produced close to the automotive assembly line, which allows for better integration and reduced transport. Aluminum castings have the potential to be almost CO² neutral when using low-CO² aluminum alloys and biogas for the melting furnaces. The aluminum that goes into overflows can be remelted directly and reused in the die-casting cell, thereby avoiding transport and recycling. Thinking a step further, the usage of lighter aluminum parts can reduce the energy consumption of the cars over their entire lifecycle.”

Volvo explains the process in a video: “The process goes like this -- molten aluminum is forced into a high-pressure mold. It solidifies as it cools and is then dipped in water to speed up the cooling process. After some laser cutting and quality checks, the parts produced using this process will eventually become part of the floor structure in our new electric [model] range.”

“This process significantly reduces the number of parts produced and allows for greater design and production flexibility,” the video continues. “Megacasting also helps our sustainability ambitions, as it reduces our environmental footprint across production, gives greater potential for recycled content, and reduces the weight of our cars, which in turn reduces energy consumption and improved energy efficiency.”

Reaping these benefits has its hurdles, however. “These high-pressure die casts, they need bigger footprints,” Began explained. “Some require a deeper hole. A traditional foundry floor isn’t big enough.”

Began toured Mercury Marine to see its installation of a gigapress and was astounded. “I remember walking into that room and hearing that this was just for one machine,” he recalled. “Something like that would normally house three machines. The building needs things like bigger doors and higher ceilings.”

Bühler acknowledges this issue on its website. “Such large solutions require proper planning, looking at the entire process, from the ingot to the body shop,” it says. “These large cells, with integrated peripherals, require a well thought-through setup. It all starts with site planning and the set-up of a process for part handling within the die-casting cell and afterward. Also, the thermal management and spraying process, clever handling of the return material, and the integration of the right peripheral devices are key.”

“Especially for such large projects, thinking about the entire die-casting cells from the melting furnace to the handling of the final part is essential,” Mendler concluded. Click through the slide show to see the complexity of this process.