Additive Manufacturing Binder Jet Aluminum 3D Printing Process shows Comparable Properties to Die Casting
In a jointly funded project between Ford Motor and ExOne, developers have now developed and filed a patent for a process for fast and reliable binder-jet 3D printing and sintering of aluminum that shows properties comparable to die casting.
Although some aluminum alloys can be already be 3D printed with lasers today, the process is slower than the new one developed by Ford and ExOne. The new process is expected to increase Ford’s efficiency by allowing the company to affordably produce complex parts uniquely designed for additive manufacturing, which enables size and weight reductions, part consolidation, and performance improvements.
“This is a breakthrough in making 3D printed and sintered parts for the auto industry,” said Harold Sears, Ford technical leader for additive manufacturing. “While the 3D-printing process is very different than stamping body panels, we understand the behavior of aluminum better today, as well as its value in light-weighting vehicles. High-speed aluminum 3D printing paves the way for other opportunities that we’re just now starting to take a look at because of the ability to do complex parts with aluminum that previously weren’t possible. It’s really opening doors for other opportunities.”
“Developing a fast, affordable, and easy way to 3D print aluminum with traditional material properties is a critical step toward light-weighting more products and delivering a more sustainable future,” said John Hartner, ExOne CEO. “Our world-class engineers and scientists are focused on solving the toughest problems with 3D printing technology, and this achievement is a real win for all of us.”
The new innovation came about through the process of binder jetting, widely regarded as the fastest method of metal 3D printing for high-volume output. It uses a digital file to quickly inkjet a binder into a bed of powder particles such as metal, sand, or ceramic to create a solid part, one thin layer at a time. When printing metals, the final bound metal part must be sintered in a furnace to fuse the particles together into a solid object. The heating process reinforces the strength and integrity of the metal, and while the process for sintering stainless steel is well understood, achieving high densities greater than 99 % is an industry breakthrough for aluminum.
The Ford-ExOne joint development project was first initiated in 2019. Ford has led the final material and repeatability testing to verify its accuracy. The cross-functional Ford-ExOne team is actively working on designs to use the new material and process.