Manufacturing Engineering: Markforged is focusing on metal additive manufacturing, but why are you also emphasizing carbon fiber and composite materials over polymers?
Tom Muscolo: While we offer polymer materials, our primary focus is on composites simply because they provide superior properties for nearly all applications, versus just a “neat” polymer. Historically, the cost, complexity, and manual labor involved in building composite parts made them cost-prohibitive for most applications, and so the default for many engineers was either polymers or metals. Our systems and the benefits you get from being able to print these composite parts on-demand have changed that math, however.
ME: Some people might be skeptical over your ability to accurately and predictably control shrink rates on your Metal X System. What do you say to them?
Muscolo: Though each part and material is different, our Eiger software automatically scales part geometry based on its predicted shrink rate during sintering. Since many readers may not be familiar with the process, it’s worth describing. Our Metal X printers use ADAM (Atomic Diffusion Additive Manufacturing), which is based on fused filament fabrication (FFF) technology. Metal powder is encased in a plastic binder and then deposited layer by layer through an extruder. The part then needs to be washed and sintered to dissolve the binder and allow the metal powders to fuse. During the sintering phase, when the metal part is almost finalized, we typically see our parts shrink about 17 percent to their final size (although this varies by material). The parts are near net shape, and most of our customers can use them right off the print bed, although they can also be post-processed like any other metal part to achieve critical dimensional tolerances or smoother surface finish. So, while in most cases the parts come out of the sintering furnace ready to use, the fact is that our shrink estimation is currently a well-tuned, but fixed approximation. This is where Blacksmith comes in, our AI-based, closed-loop process control software, which automatically takes scanned part measurements and adjusts how the Metal X prints to compensate for any deviations.
ME: You seem to place an emphasis on 3D-printed tooling for use in machine shops and fabricating houses. Why would a manufacturer choose your solution over traditional gages, fixtures, and jigs?
Muscolo: In the vast majority of cases, we see the best use for additive manufacturing not in replacing traditional manufacturing, but in supporting it. By introducing a 3D printer into a shop, manufacturers can move faster, be more flexible, increase uptime, and reduce costs. The process of designing, prototyping, and fabricating the traditional gages, fixtures, and jigs needed to manufacture a customer’s parts can be one of the most expensive and time-consuming parts of a job. Lead times can stretch to weeks or months. Costs can soar into the tens of thousands of dollars. Any time you (or your customer) need to make a change, it means costly rework or starting over, not to mention throwing a wrench into your shop schedule. With 3D printing, however, you can iterate on tooling designs at low cost, without tying up valuable shop resources, and far more quickly than with subtractive processes.
ME: Setting aside the role of CAD and generative design tools, what role does software play in additive manufacturing?
Muscolo: 3D printing is as much about the software as it is about the unique technology of the printers, and a well-designed platform brings the power of agile software engineering to the world of industrial manufacturing. Far more than an industrial 3D printer, it’s a robust, code-first platform that glues together hardware and materials with the power of the cloud to continuously improve itself. This fully digital workflow is the only way to quickly and seamlessly go from design to part to application. While part design is a critical aspect of 3D printing software, any platform without automatic version control, real-time fleet management, and cloud-based collaboration fails to maximize your hardware.
ME: Your company is a relative newcomer to the market and has seen rapid growth over the past few years. Where do you see yourselves in 10 years?
Muscolo: With the future of additive manufacturing overhyped for so long, it’s easy to be fatigued by talks of what’s next. Other companies spent years overpromising additive manufacturing as the coming of a new industrial revolution, but that shift is not as simple as flipping a switch. Manufacturing as a collective industry is about 10 years into its additive journey; at Markforged, we expect the next 10 years to be a time where additive technologies continue to be adopted. The value of 3D printing is clear—it allows manufacturers to pivot and address new needs as they emerge, capabilities proven to be more critical today than ever. We’ve just begun to scratch the surface of additive’s applications and the industry is sure to realize further uses for the technology—especially as we work more closely with customers to address applications that must pass the industry’s most stringent certification standards.
ME: Many 3D printing equipment manufacturers—especially those making laser-based metal powder bed machines—are placing a great deal of emphasis on in-process metrology and monitoring. Where does Markforged stand on the question of quality control?
Muscolo: Quality is of course important to us, and there are several aspects of our systems that help ensure our customers consistently get parts that meet their quality standards. The first is that we develop, manufacture, and support the full stack of hardware, software, and materials needed to print. The interactions between these three components is critical to final part quality, and having control over each means we’re better able to tune them to work together.
Second, the material extrusion technologies that we use in composites and metal are inherently simple, yet robust. Competing technologies require a high level of in-process metrology because the physics of using a laser to melt metal particles is incredibly complex. By contrast, our Metal X system first forms a part (green-state) via FFF, that is then placed into our furnace and sintered the way powder metal parts have been sintered for decades.
Finally, inspection and closed-loop feedback control is key for ensuring quality. The laser onboard our X7 measures and compensates for variation and inspects parts while they’re being manufactured to confirm accuracy. And our Blacksmith software uses AI to compare a 3D scan of your as-printed part to your as-intended part and automatically compensates for any deviations from nominal that may be a result of printing or sintering.
ME: In previous discussions, you’ve mentioned that artificial intelligence (AI) will become an increasingly important part of additive manufacturing. How so?
Muscolo: Software is a critical part of any additive manufacturing platform, but to unlock the true value of 3D printing, it’s crucial that software is an embedded piece of the puzzle and not just an afterthought or add-on solution. Essentially, AI and software solutions make the entire process easier by removing the manual, complicated aspects of printing. By pairing cloud-based 3D printer design with fleet management software, they can leverage a continuous feedback loop to make 3D printed parts more accurate, a process we’ve dubbed adaptive manufacturing.
ME: You recently announced the addition of copper to your metals portfolio. Why is this important, and can you name any target applications?
Muscolo: We’re excited to be offering manufacturers the ability to print high-purity copper. Because of its electrical and thermal conductivity, copper is the first choice in many manufacturing functions—from spot welding in automotive to heat sinks in electronics—but it is both expensive and challenging to machine, especially for low-volume applications. Now, manufacturers can 3D print copper quickly, easily, and for a fraction of the cost of traditional methods—allowing them to save on production cost and further streamline their supply chains.
In a joint press release, Heraeus Amloy, Hanau, Germany, and Trumpf, Ditzingen, Germany, announced that the additive manufacturing industry now has yet another advanced material at its disposal: metallic glass. These amorphous metals are formed by cooling molten metal extremely quickly and are said to be twice as strong as steel, yet significantly lighter and more elastic. They also exhibit isotropic behavior, which means their material properties remain identical, regardless of the direction in which the 3D printer builds up the workpiece. This makes amorphous metals ideal for lightweight parts subject to significant stresses, such as those used in aerospace and mechanical engineering. Because they are biocompatible, amorphous metals can be used in medical devices as well.
Manufacturing professionals looking to learn about the latest in advanced 3D printing materials will want to download the latest eBook from AM industry media firm 3dpbm, Farnham, Surrey, UK, the company’s fourth book so far. Within its 50 pages, readers will learn about technical ceramics, continuous fiber-filled composites, refractory metals, high-performance polymers, and other cutting edge materials used in the aerospace, automotive, defense, medical, electronics, and dental industries, among others.
Along the same lines, 3D printing products and services provider PADT has launched an online glossary of industry terms relevant to additive manufacturing. The new site (www.3dprinting-glossary.com) defines more than 250 terms in nine different categories and strives to make sense of the many acronyms used in AM.
“Our goal for the glossary is to help educate the community on the evolving terminology in our industry and serve as a critical resource for students and professionals seeking 3D printing knowledge and clarification,” said Eric Miller, co-founder and principal, PADT. Feedback is encouraged.
In early April, SLM Solutions Group AG, Lübeck, Germany, announced the formation of a strategic partnership with Canwell Medical Ltd., a medical device manufacturer in China. Canwell will leverage SLM’s experience in printing acetabular cups, intervertebral fusion cages, and other medical components made of titanium and cobalt-chrome alloys, thereby hoping to accelerate the product certification and serial production phases for its line of orthopedic implants. “Our global experience accumulation and innovation will help us further develop China’s medical field,” said Jerry Ma, general manager of SLM Solutions Asia Pacific.
VELO3D Inc., Campbell, Calif., announced its plans for a next-generation Sapphire industrial 3D metal printer with a vertical axis of 1 m (39.37"), reportedly “the world’s tallest production metal-powder laser additive manufacturing system.” The system will ship in Q4 2020, with tool and component manufacturer Knust-Godwin LLC, Katy, Texas, securing the first order. Among the first jobs planned for the machine is an oil and gas part that currently requires five machining steps to complete.
According to Will Richardson, co-founder and CEO of Wayland Additive, existing metal powder bed fusion (PBF) technology is limited. Those that use lasers to fuse metal particles produce the highest part fidelity and best surface finishes but generate internal residual stresses that lead to part distortion and cracking, thus requiring extensive structural supports and post-build heat treatment to avoid. Electron beam (eBeam) processes reportedly fare better in this respect and are faster, but are prone to charge accumulation within the build chamber. This can cause powder scattering or so-called “smoke events” that distort the current build layer and hurt part quality.
It’s for these reasons that Richardson’s company has been working on the development of a new PBF process for metal AM dubbed NeuBeam, a “hot part process” that reportedly neutralizes the charge accumulation generated by the electron beam. “This offers greater flexibility than laser PBF while overcoming the stability issues of eBeam PBF,” Richard said. “What’s more, NeuBeam better enables a part’s metallurgical properties to be tailored to the application requirements, rather than being limited to the narrow bounds permitted by existing technologies. The result is parts that are free of residual stresses, free-flowing powder post-build (no sinter cake), faster build speeds, and reduced energy consumption.”
AM equipment and software supplier Optomec has added aluminum to its line of 3D printing materials (which includes steel, stainless steel, titanium, nickel, and copper) for use in its LENS Directed Energy Deposition (DED) systems. Optomec says this development opens the door to transportation and aerospace applications, as well as the repair of complex aluminum alloy parts. This is made possible via a controlled atmosphere “glove-box” with very low levels of oxygen and moisture, allowing the five-axis LENS (laser engineered net shaping) to process complex aluminum alloy parts without the need for support structures, and “ensures achievement of components with superior mechanical properties,” said Optomec.
Additive Manufacturing Update is edited by Contributing Editor Kip Hanson; kip@kahmco.net
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