Discussions of additive manufacturing invariably turn to prototyping for a good reason: economics. While it may make sense from a cost perspective to 3D print functional new parts with plastic or metal during the design process, additive manufacturing (AM) techniques cease where mass production begins.
Few manufacturers are discussing replacing traditional production methods for parts with AM techniques, as it would simply be too expensive. For plastics 3D printing will probably never beat the speed and volume capacity of injection molding. (However, using AM to create the molds will lead to more rapid product innovation with plastics by eliminating the single biggest bottleneck in the injection molding process.)
There are companies today working to change the economic equation and bring down the costs of additive manufacturing so AM techniques could be feasibly pushed out to more applications and higher volumes, and this is particularly exciting for metal parts manufacturing. The rise of lower-cost metal printers offers manufacturers excellent part quality that minimizes expensive post-processing to keep a check on costs.
In 2014, Cambridge, Massachusetts-based Markforged shook up the additive manufacturing industry with the introduction of the world’s first carbon-fiber composite 3D printer. Earlier this year at the Consumer Electronics Show (CES), company CEO and MIT aerospace engineer Greg Mark unveiled the company’s Metal X desktop printer, which, once it becomes available in September, will print in a variety of metals including 17-4 stainless steel, 303 stainless steel, 6061 aluminum, 7075 aluminum, A-2 tool steel, D-2 tool steel, IN alloy (Inconel) 625 and titanium Ti-6Al-4V. The printer speeds up production with rapid sintering using a microwave furnace, a process that becomes highly reliable when the printer is following consistent instructions. Designs are printed in metal powder surrounded by plastic, the plastic is dissolved and the metal is sintered, leaving behind a strong metal part.
The driving technology behind the Metal X printer is a process Markforged calls “Atomic Diffusion Additive Manufacturing (ADAM).” ADAM, according to VP of Marketing Cynthia Gumbert, is at the intersection of 3D printing and metal injection molding and blends high part quality with complex available geometries and high density.
“ADAM is in fact very similar to the chopped carbon fiber (Onyx) printing process Markforged introduced, with bound powdered metal rather than bound tiny pieces of carbon,” Gumbert told Design News. “We call the Metal X our fourth-generation printer because so much is already used in our carbon fiber printers. The focus on excellent surface finish and dimensional accuracy has carried over from our plastics printers to make this unique in the metal additive industry.”
|Image of a 3D-printed brake lever. Photo credit: Markforged.|
The company predicts that its ADAM print technology will evolve over the next months and years into a product lineup of even more affordable and scalable printers, with the “blade server” concept for volume manufacturing where printers on a rack will scale up or down to meet customers’ needs, as they do in current server farms.
The company’s printers operate on its proprietary Eiger printer software, and Gumbert noted that the company invites regular feedback and input from its installed user base and adds capabilities to meet their needs, particularly at the design level.
“We’ve most recently added part weight, materials usage, time to print as well as cost of materials so users will get all those parameters before printing and with the ability still to make changes to the design,” she said.
Interestingly, the Eiger printer software is designed to manage printer fleets, which it already does with the company’s composites printers. Earlier this year, CEO Greg Mark told the audience at CES that the future of metal 3D printing is in print farms. The Metal X printer was created as an affordable ($99,500 is the current price tag) standalone shop printer, but the company sees a vision of fleets of these printers operating in tandem.
“Our Metal X printer is the first step in this direction,” Gumbert told Design News. “It’s not in the same category of the large-format metal printers that form a high-end, expensive niche that only larger manufacturers can afford. Parallelization is the key to scaling volume, rather than a different, faster type of print process. We’ve always been about getting a near-final or finished piece right off the printer that can be sintered with very little post-processing, and ADAM is generating extremely high-quality parts.”
To serve the needs of smaller manufacturers, the company envisions “print farms” as small as just a handful of printers, or a single Metal X. Distributed companies or service shops could have a version of a “print farm” with no two printers at the same location but the ability to access distributed machines through the Eiger software to create a coordinated global array of printer instances.
Going forward, further automation of print farms is likely to involve robotics. There are already companies using robotics in AM either to control the print heads that deposit materials or even as a way to facilitate an automated end-to-end additive manufacturing solution.
“Scaling anything for production goes hand in hand with automating as much as possible to bring speed and efficiency,” said Gumbert. “Right now, parts are removed by hand from our printers, but don’t expect that to be the case forever.”