It was only six months ago that aftermarket wheel company HRE revealed that it was developing the world's first 3D-printed titanium wheels. Since its initial prototype, the company has been diligently working to improve upon the manufacturing process and officially announced on Tuesday that it had developed a new, second-generation HRE3D+ wheel. To make things even cooler, the wheels were unveiled on IndyCar star Graham Rahal's dazzling Ford GT. HRE continued this project with the help of General Electric's additive manufacturing division, GE Additive. Together, the two teams worked to refine structural decisions, slowly combing through design improvements and changing the fine details of the wheels.

via YouTube

The first generation of the HRE3D+ was printed using a process called Direct Metal Laser Melting which works by melting ultra-fine layers of titanium powder on top of one another. Eventually, a solid and complex shape takes form to make up the final product. HRE and GE changed this up with the second generation of printing, switching to a more refined method of printing called Electron Beam Melting. This fused-fabrication process works by using a 3,000-watt or 6,000-watt electron-beam gun to melt the titanium powder whilst in a high-temperature vacuum environment. The end result is a component that has been stress-relieved and has a higher hardness than both cast and wrought alloys by a factor of nearly two. The second generation wheel also significantly improves upon the reduction of waste material. Previously, HRE says that nearly 80 percent of the raw titanium (by weight) used during manufacturing was considered to be waste. Using its new process, that number has been reduced to just five percent.

via HRE The HRE3D+ is now comprised of five cross-sections that sit within the inner barrel, down from six in the first generation.