A production revolution?

Two very different technologies make up much of the fast-growing world of additive manufacturing (AM). One uses a laser and emerges out of the stereo lithography (SL) sphere of 25 years ago, which was initially focused on prototyping. However, today’s 3-D printing machines are used for production runs as well, particularly when selective laser sintering and selective laser melting. The other major AM technology uses P/M and electron beams to produce parts.

Terry Wohlers, president of AM consultancy Wohlers Associates Inc., Fort Collins, Colo., said these additive technologies “will have a profound impact on manufacturing in coming years. They may become more important and useful than CNC machinery, injection molding and other conventional methods of manufacturing.”

Although previously slow, AM processes are getting faster. “For small plastic parts, you can produce more than 1,000 parts a day with some 3-D printers and as many as 300 parts per day with electron beam machines,” Wohlers said.

Airbus, for example, is considering the use of AM for metal brackets, and Boeing uses plastic parts made on AM machinery for its military aircraft and the 787 Dreamliner, according to Wohlers.

Regarding metal parts, AM is suitable for producing ones made of various alloys. For instance, Cincinnati- based Morris Technologies, along with its sister company Rapid Quality Manufacturing Inc., has 20 AM machines for making aluminum, stainless, cobalt-chromium, Inconel and titanium parts. CEO Greg Morris noted that his company, which reportedly introduced direct metal laser sintering to the North American market in 2003, began in SL and is familiar with numerous AM technologies. The virtue of AM “is its ability to produce complex parts faster and less expensively than conventional methodologies,” he said.

The vast array of AM technologies, however, can create confusion. “People often discuss the AM industry as one entity. We at Arcam don’t think that is totally correct,” said Magnus René, CEO of Arcam AB, Mölndal, Sweden, adding that Arcam’s equipment has little in common with the machines from some other AM machine builders. He noted that Arcam’s machines can produce metal parts up to 300mm in diameter and 200mm high, and some of its machines are producing 10,000 medical components annually.

The medical and dental parts produced with AM can facilitate life-changing events. “We printed the medical model that was used to separate conjoined twins attached at the head,” said Cathy Lewis, vice president, global marketing for 3D Systems Corp., Rock Hill, S.C. “In partnership with our customers, we helped revolutionize the hearing aid industry from off-the-shelf to custom shells using 3-D printing, and we produce tens of thousands of clear aligners every day that are used to straighten teeth instead of traditional metal braces.”

What’s coming? In the next several years, Lewis expects the technology to progress in several core areas. She said: “Material science will continue to advance along with the technology, allowing even more end-use manufacturing. Special biomaterials will become available with FDA approval. More health care practitioners will become knowledgeable about the potential of 3-D printers and, when paired with the right technology, this will enable expanded medical and dental applications. Price, availability and ease of use will converge to provide the power of 3-D printing to a far broader audience than we see today, including the consumer.”

AM technologies have been developing for about 25 years and offer options for almost any shop. Although they won’t eliminate metalcutting machine tools in the foreseeable future, they will make shop managers think twice about which technology they should acquire, according to Arcam’s René. “AM and conventional technologies like casting and machining will coexist,” he said. “Compare this to laser cutting and waterjet cutting. These are two relatively new methods and they both coexist with each other and together with traditional cutting.”

To make further inroads into production manufacturing, AM research continues. In Europe, the Fraunhofer Institute’s Fraunhofer Additive Manufacturing Alliance created “the largest interdisciplinary European alliance of competence for high-speed processes, enabling individual manufacturing of products made of metals, ceramics and other materials,” stated the Aachen, Germany- based institute.

In the U.S., General Electric recently established a laboratory in Niskayuna, N.Y., dedicated to AM research. According to lab manager Prabhjot Singh, AM has the potential to be a disruptive manufacturing technology. “It has a great deal of potential, especially for complex parts,” he said.

—George Weimer