Unsprung weight is a real issue for high-performance automobiles. Unsprung weight is defined as anything directly connected to the wheels such as tires, brake assemblies, differential, solid drive axles, hub motors, and of course the wheels themselves. Any reduction in unsprung weight has a tremendous effect on the performance of the vehicle. Aluminum and magnesium alloys are the materials of choice for producing lightweight wheels for the automotive industry. The ideal material for wheels would be titanium, given its incredible strength and light weight, but it’s titanium’s strength that makes it difficult to machine into the complex shapes used in modern wheels. This combined with a high melting point which makes it very difficult to weld, have put titanium out of the wheel business. Until now. Behold the HRE3D+ wheels from HRE Performance.
HRE Wheels, a performance wheel manufacturer founded in 1978 in California, has teamed up with GE Additive to develop the first 3D printed titanium wheel. The wheels are made using GE’s EMB Machines, specifically the Arcam EBM Q20plus. These machines use electron beams to melt a pile of titanium powder layer by layer which allows them to “print” shapes far more complex than previously possible using traditional CNC techniques. In addition to the more complex parts, the process leaves only 5% of the powdered titanium waste (which is recycled) after the part is complete. CNC machining involves removing up to 80% of the original 100 lb forged block to create just one wheel. The new method is also 15% faster than CNC machining.
“This is an incredibly exciting and important project for us as we get a glimpse into what the future of wheel design holds,” said HRE President Alan Peltier. “Working with GE Additive’s AddWorks team gave us access to the latest additive technology and an amazing team of engineers, allowing us to push the boundaries of wheel design beyond anything possible with current methods. To HRE, this partnership with GE Additive moves us into the future.”
The Arcam EBM Q20plus created 5 individual, complex parts which are then attached to a carbon fiber rim to complete wheel. Due to its exceptional corrosion resistance, the titanium wheel needs no additional coatings to protect it from the elements.
The first prototypes are being showcased on the British supercar, the McLaren P1. HRE did not provide a final weight, or speculate on the feasibility of putting these wheels into mass production.