At the University of Wisconsin-Madison’s Grainger Institute for Engineering, bringing metal additive manufacturing to the mainstream is a major goal. Dr. Dan Thoma, the Director of the Institute, provides an overview presentation to describe the strengths and opportunities within the Metal Additive Manufacturing nascent industry.
Additive manufacturing (AM) has captured the imagination, Dr. Thoma mentions, and in turn, has also captured the attention of a number of global organizations as a technology that could provide game-changing solutions to current societal problems. There is much interest in advancing this new area of manufacturing, and quite a bit of investment into improving the technologies.
At today’s technology capabilities, only low volume but high expense parts are economically viable to be manufactured using AM. However, for some components, the payoff is huge. One of the first success stories for production-value AM is the GE Fuel Nozzle for LEAP engines. This internally complex part is the ideal item to be manufactured by AM – there is a low volume need for the part, but once made, can save on the order of millions of dollars of fuel costs when used in a GE engine. GE estimates that it will manufacture over 100,000 parts by AM by 2020 and has over 300 3-D printing machines operational across GE worldwide.
Three different metal AM techniques are described: Selective Laser Sintering (also known as Powder Bed), Laser power fusions LENS, and Electron beam Additive Manufacturing (EBAM, wire). These three methods are schematically represented in his presentation, and during the webinar, Dr. Thoma shows videos of the techniques in action.
Dr. Thoma also covers the many challenges being faced by additive manufacturing, including cost and value, waste, feedstock, surface finish, residual stress, and qualification. For example, he discusses selective laser sintering as an example that provides the best part finish and accuracy in manufacture, but also defined the needs for standards; currently, machine to machine repeatability for the same processes is low.
Before transitioning from the challenges facing metal additive manufacturing to the opportunities it presents, Dr. Thoma notes that because of the excitement around the opportunities, “There is a tendency to oversell the technology.” He then discusses the opportunities of the technology from the view of a material scientist; that is, the opportunity to design products in a 3-D way while being able to vary properties of the material during processing. This allows the materials engineer to design for performance in a predictive way.
The conclusion of the talk sums up that the history of additive manufacturing has evolved to a point where digital control, cost and availability of equipment promotes the viability of the technology. While challenges still exist, the opportunities provided are exciting and truly trans-disciplinary.