A new “Turbu pressure casting” process can be used to produce aluminum wheels for cars that are more stable, lighter and thinner than previous wheels. Production requires a quarter fewer raw materials and only half as much energy. This makes the economical light alloy wheels more attractive for car manufacturers and more sustainable and environmentally friendly than previous models. The inventor was awarded the German Innovation Prize 2025 for this. The bikes are scheduled to go into series production as early as 2026.
The engineer Ralf Bux, founder of the medium-sized company Entec-Stracon in Aalen, Swabia, has developed a new manufacturing process for aluminum car wheels. This has so many advantages that the inventor was honored with the German Innovation Prize 2025 in March. The process he developed is called “low-turbulence pressurized casting,” or “turbu-pressure casting” for short, and relies on very high pressure and speed during production: “In turbo-pressure casting, the aluminum alloy shoots sideways into the mold under high pressure within a fraction of a second,” says Bux. The company only needs 0.05 seconds to cast a wheel.
More resource-saving, more stable and lighter
In conventional low-pressure casting, however, the molten aluminum alloy flows slowly from the center into the mold and is distributed using gravity. It is then cooled and excess material is removed from the edges. Although “Turbu pressure casting” also produces metal shavings as waste, these are of higher quality and can easily be reused for the next casting. Hundreds of sensors in quality control also monitor production continuously and closely, so that there is little to no waste. The bottom line is that the process requires around 25 percent less raw materials and is therefore significantly more resource-efficient and cost-effective than low-pressure casting.
Further advantages: “Due to the high speed and the extremely low tool temperature after solidification, the material has significantly smaller grain sizes and therefore higher strength and elongation,” explains Bux. The new light alloy wheels are therefore significantly more stable and stronger than before and can also be shaped and designed more flexibly. An important argument because many car buyers pay attention to a delicate design. The new aluminum wheels are also thinner and lighter: “Thin-walled cross-sections are possible thanks to the close-contour casting,” says Bux. In times when cars are becoming larger and heavier, it pays off if at least individual components such as the wheels become lighter. Because that saves fuel when driving. In the end, drivers of cars with economical light alloy wheels also benefit.
Energy consumption halved
In addition, the new casting process requires less energy than before: “With our production we need 57 kilowatt hours per wheel instead of the usual 114. The process reduces energy consumption by half,” says Bux. This means the company can save nine gigawatt hours of electricity per year – this corresponds to the energy needs of more than 2,200 four-person households. According to Bux company Entec-Stracon, the energy for wheel production comes from sustainable sources and does not use climate-damaging energy sources such as gas. This low-energy process reduces greenhouse gas emissions from wheel production, which reduces the burden on the environment.
The first cars from BMW and Mercedes will soon be driving with the new aluminum wheels. In the future, even more vehicles from these and other automobile manufacturers will be equipped with them. Each Entec-Stracon casting machine can produce more than 150,000 wheels annually. The aluminum wheels are scheduled to be mass produced there as early as 2026. If the wheels prove successful, “turbu-pressure casting” could completely replace low-pressure casting in the long term.
Source: German Federal Environmental Foundation (DBU)