So Prorok and his colleagues Lewis Payton and Tony Overfelt built their own. Combining a metal inert gas (MIG) welder, which melts thin wires of metal in a protective CO2 atmosphere, and a computer numerical control system typically used in the automation of machine tools, they engineered a prototype printer that was able to create finished products by fusing layer after layer of MIG-melted metal together. Students couldn’t use the system to build anything too complicated, but at least it was a start. “You can teach kids in the classroom, but it’s not until they get hands-on training that they really begin to learn,” Prorok says.
Last year, Prorok and Overfelt applied to GE’s Additive Education Program, and Auburn became one of eight colleges and universities to receive a direct metal laser melting (DMLM) machine — a state-of-the-art 3D metal printer made by Concept Laser, a company GE acquired in 2016. The machine uses a laser to fuse layers of metal powder together to print parts directly from computer files.
When the machine arrived last December, Prorok and his excited students gathered around to watch the first print — an impeller, which is the rotating part of a pump for a centrifuge. “I don’t want to say the exact words I said at the time, because you can’t print them,” laughs Prorok. “But we were all just amazed.”
Since then, he’s let his students run wild with their imaginations. Within limits, of course. While Prorok believes mistakes help people learn, he doesn’t want to waste valuable metal powder on projects that are destined to fail. His students have been building metal meshes for medical use that could help hold implants in place. Those just starting to learn the ins and outs of the DMLM machine create Lego bricks. “Whenever we have high school kids come to tour the lab, they always love to pick up the metal Lego bricks,” says Prorok.
In July, the machine helped another group of students at Auburn win the American Society of Mechanical Engineers’ ASME Student Design Challenge to build a better heat sink, a device that takes heat away from electronics so they don’t overheat. Working with Sushil Bhavnani, a professor of mechanical engineering, the students designed a finned device that looks sort of like a metal seaweed garden, with tendrils rising from a base. The sink is meant to sit on a piece of electronics and conduct heat toward a fan. While most heat sinks have fins that taper as they move away from the base, the students were able to use 3D printing to design fins that instead grow wider, making them more efficient.
Prorok’s students printed the heat sink that Bhavnani’s team took to San Francisco for the challenge finals. “What set ours apart is the heat sink had multiple features that made it very efficient, but it could not have been built using conventional techniques,” Bhavnani says.
Auburn is just one school that’s reaping the benefits of teaching additive manufacturing. Last year, in addition to DMLM machines, GE Additive distributed more than 400 plastic-based desktop 3D printers to elementary, middle and high schools worldwide. GE estimates that 180,000 students now have access to 3D printers thanks to the Additive Education Program. GE plans to invest $10 million over five years in the program. Applications for the 2018 program are due Feb. 28 and can be found at the GE Additive website.
Greg Morris, additive technologies leader at GE Aviation, came up with the idea for the program with the aim to get more kids interested in STEM education. “We want to get their attention and show them science can be really cool,” Morris says.
At the college level, he hopes the printers will help students get the skills they need to fill the growing number of job openings within additive manufacturing. Morris’ company, Morris Technologies, was an innovator in additive technologies. Employees at the company worked with GE Aviation to design and build a 3D-printed fuel nozzle for the LEAP engine. The design combined 20 parts of the complicated piece of machinery into one, which weighs 25 percent less than traditional fuel nozzles. GE bought Morris Technologies in 2012.
GE now manufactures the LEAP nozzle in Auburn, Alabama, not far from Prorok’s classroom. “I think some of the kids will end up working there,” Prorok says. As more and more students learn about additive manufacturing through machines in their classrooms, Prorok’s kids are only the first wave.