Above: EOS uses additive manufacturing to laser sinter parts.

Additive manufacturing pioneer shows industries how to gain their design freedom while eliminating tooling costs and fabrication steps

April 2017 - A magic triangle asks math enthusiasts to arrange a number sequence [1 - 6 for a 3 x 3 x 3 triangle] for each triangle so that the sum of numbers on each side is equal to the sum on every other side. The exercise is designed to cultivate logical thinking skills and mental calculations. 

EOS of North America Inc. is using its own version of a magic triangle—machine, material and processes—to grow its customer base for additive manufacturing and direct metal laser sintering (DMLS). The Novi, Michigan, company performs industrial 3D printing of metals and polymers. 

Physicist Dr. Hans Langer founded EOS in 1989 after observing a trend among research institutes in the U.S., Europe and Japan. The focus he noted was trained on a new technology: “Manufacturing layer by layer with the aid of laser equipment based on 3D data. I was fascinated by this. I imagined what it might mean to produce components. Part complexity wouldn’t play a role and there would be no tooling requirements.”

Holistic approach

As a core component of additive manufacturing, DMLS uses a Yb (Ytterbium) fiber laser that is fired into a bed of powdered metal. The laser’s beam is focused on multiple points in space, as defined by a 3D model, and then welds or fuses material together to create a solid structure. The printer platform is then lowered, another layer of powder is applied and fused to bond with the layer below. This process continues until the part is completed. 

EOS’ selection of metal powders ranges from aluminum, maraging steel and high-grade steel to titanium, nickel and cobalt chrome alloys. 

“Every customer is facing the same challenge,” says Glynn Fletcher, president of EOS. “Whether a manufacturer is competing locally, nationally or internationally, they are looking for a lower cost production environment. Additive manufacturing gives you the ability to do things differently.”

EOS takes a holistic approach with customers by working closely with them to understand their challenges and then develop solutions that are competitive when compared to those available in the marketplace. GE Aviation is one example. In 2015, the aerospace manufacturer completed a multi-year project to print a working jet engine. EOS’ M270 model 3D printer was used to build more than a dozen parts. And because the machine can melt different alloys, the technology allowed GE engineers to use high-temperature alloys.

“Our technology also freed engineers to design the nozzles on the LEAP jet engine as one part versus 20 individual parts,” Fletcher says. “This meant they could eliminate steps like the number of welds that a traditional fabrication method would require.” 

EOS uses additive manufacturing to laser sinter parts like this aluminum automotive heat exchanger (below, left), liquid lattice design (below, right) and aluminum satellite antenna bracket (above).

Weighing in

In January 2017, EOS formed a development partnership with Audi AG. EOS is supporting the automaker with integration of its 3D printing technology and development of a 3D technology center in Ingolstadt, Germany.

“The aim is not only to supply Audi with the right additive systems and processes, but to also support them during applications development, while building up internal additive manufacturing knowledge and training their engineers to become in-house experts,” said EOS Global Application and Consulting Director Güngör Kara said in a statement.

Despite adoption by industry titans like GE and Audi, Fletcher says there are some barriers the budding technology still has to cross. “There are not too many things that you can make with conventional forming and fabricating that you can’t make with additive manufacturing,” he says. “Any metal item that fits a 16 in. by 16 in. cube can be made with additive manufacturing.”

However, there is a deeply rooted, huge infrastructure that supports traditional manufacturing methods. “Change is hard,” says Fletcher, “because everyone has so much invested in their current resources.”

Competing against what some might call “old habits,” the requirements for DMLS are simple. “You turn a laser on some powder and make a product,” Fletcher says. “You don’t need a large infrastructure or a huge amount of raw material. You don’t need other forming and fabricating machines, such as milling, cutting and bending.”

The technology also moves products to market faster. “Early to market businesses generally are the ones that thrive,” says Fletcher.

The EOS M 400-4 metal additive manufacturing machine, supported by DMLS, anchors the company's holistic approach with customers.

Spares on demand

“In metal, parts are designed with specifications for things like right angles,” he continues. “With additive manufacturing, you have design freedom. You can integrate functionality versus assembly of multiple parts. Capital investment is reduced and so are tooling costs.”

Additive manufacturing and DLMS provide important tools customers can use to optimize their supply chains. Production can be localized.  “Making spares on demand becomes realistic with additive manufacturing,” says Fletcher. “You could make parts in the middle of the Sahara or on a submarine. The cost of working capital linked to carried inventory becomes moot.”

Although EOS is finding applications for its technology in nearly every walk of life, the company is especially interested in industries that produce high value, complex parts such as aerospace, automotive and medical devices. 

“It’s a more sustainable process because you are producing near-net shape parts,” Fletcher says. 3D printing allows a judicious use of material—high yield, little or no scrapping.

Manufacturing has long been touted by economists as the pathway to fostering innovation, boosting competitiveness and raising living standards. EOS recognizes the potential for additive manufacturing powered by DMLS in the movement toward digitized production. “It’s a digital process,” Fletcher confirms. In addition to a changing manufacturing culture, EOS wants to change the way designers think about making products. 

“When you look at the advantages, I don’t think there is a corporation in the world that isn’t at least curious about additive manufacturing, not only for rapid prototype applications but for production,” he adds. “We’re printing everything these days from tiny, intricate parts to body panels for cars. And early adopters willing to break with convention are seeing the benefits.” FFJ