The Oak Ridge team has a lot of capabilities in materials and processes to help in formulating the right type of materials with carbon fibers. Last year, the lab established a carbon fiber composites consortium. Since carbon fiber composites made out of autoclave with FDM represents a major shift, development will proceed in stages.
During the first 18 months or so, the partners will determine how to put milled, or chopped, carbon fiber in thermoplastics in an FDM process, and how to tailor the material's mechanical properties. The next stage will extend to the three-year mark and perhaps beyond. This will focus on laying down continuous carbon fiber on a center line of plastic wire, depositing that and growing it with the FDM process, and cutting it. "Since you can lay fiber in multiple directions, we'll take advantage of all the known statistical composite analysis tools, and integrate them into the FDM process," said DeGrange.
FDM is better suited to this project than other additive manufacturing techniques because it's one of the easiest to bring new materials to, especially multifunctional or filled materials, and for delivering them as a filament feedstock, said DeGrange. "It's easier to put carbon-loaded materials in a plastic line and maintain homogeneous repeatability than it would be to try this in a powder bed, for example."
Both methods have advantages, but when filling up a powder bed system with most plastics, the materials typically can't be recycled. The spectrum of thermoplastic materials that can be run in FDM is broader than with powder, and there's very little waste.
Customization is also key, particularly for orthotics/prosthetics.
Note, too, that this is a commercial application. There is research being conducted on other composites, including functionally-gradient ones, that use extrusion-based deposition.
Jim, thanks for that very specific injection molding example. Since Stratasys and Oak Ridge are at the beginning of the 3D-produced carbon composites research project, they're still defining parameters and performance targets. In composite manufacturing, there are a lot of variables and everything's contextual.
Recalling a particularly high-volume job I once designed, being a fully-automated 2-cavity, injection molding operation which produced a thin-walled plastic cell-phone housing at a molding cycle time of about 20 seconds ,,,,, That's 6 parts/minute.
So the point raised about production molding cycle time vs FDM cycle time is a very valid point; and that 2 cavity example was a run-rate that I truly doubt any deposition process could ever match, (let alone, exceed).
But the tool cost of that set-up was around $280,000 as I recall, and the deposition process set-up is nearly zero by comparison; so we need to remember all of the variables in the equation for economy.
I applaud and eagerly watch the FDM experiments advance.
Since they're working on both materials and processes, like those researching non-3D assembly, the material will most likely not involve resins that need to be cured. Many of the attempts at automating carbon fiber composite production are either developing much faster-drying resins, or avoiding them entirely. Regarding increasing speed, well, that's the main point of this research.
A lot depends on how much, fast it can put material down. Unless very quick or only 1-3 units needed, it's going to be hard to beat using molds either either hand or machin layup.
Now with the mold making by machine/Cad, making a mold costs little inhouse leaving little start up costs in that technic.
Whether it needs an autoclave depends on the resin chosen mostly.
But even their the mold can be designed to be heated so spray fibered resin by hand or machine and be it's own autoclave taking little more room. It's how I normally handle faster curing. Since most curing produce their own heat just insulation could do with many resins.
The range of printed items from so many new materials including metals will change a lot of things but is likely too slow compared to well done mass production, at least for now.
Jim, considering all the hassles involved, not to mention costs, of producing carbon composites and all the R&D being pursued for faster, cheaper production methods, it boggles the mind that we could simply solve the problem by making them with FDM. But why not? This project is aiming not just dollars but some pretty creative and experienced brains at the problem. Maybe you're right: if we can solve this problem, then maybe FDM can be applied to a lot of other materials not considered before for AM techniques.
Really a fantastic concept, Ann. When I think back to the first days of rapid prototyping and remember wondering "who came up with the idea of solidifying liquid polymer with a laser?" Then, I look at this technology effort and am confident that it, too, will succeed as just one more example in our human journey of discovery. The explanation of the spindle-like carbon fibers being delivered via a filament brought a pretty clear image of intent, and I don't doubt they will eventually accomplish their goal. What a fantastic thought, really; perhaps we can eventually FDM virtually any material?
Yes, TJ, that's one of the biggest deals about this project. Autoclave ovens are big, expensive and slow. Getting rid of them in one way or another is one of the goals behind several different research projects on speeding up carbon composite production, including this one we reported on earlier this year: http://www.designnews.com/document.asp?doc_id=239474 "Out of autoclave" is to composite production a bit like "Open sesame" was for Aladdin trying to open the cave.
Ann, the article uses the term "out of autoclave" several times. Does this mean the composite parts are fabricated without the use of an autoclave for curing?
Inspired by the hooks a parasitic worm uses to penetrate its host's intestines, the Karp Lab has invented a flexible adhesive patch covered with microneedles that adheres well to wet, soft tissues, but doesn't cause damage when removed.
Engineers at the University of California, San Diego are designing a robotic arm that takes inspiration from the loose, flexible, yet very strong structure of the armored plates on a seahorse's tail.
Researchers at the Missouri University of Science & Technology have designed a new nanoscale material that can transmit light faster than the 186,000 miles per second it usually takes to travel through air.
It has often been said that as California goes, so goes the nation. This spring, the state's wind power is setting energy generation records and solar energy generation is expected to rise sharply during the second half of 2013.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
A quick look into the merger of two powerhouse 3D printing OEMs and the new leader in rapid prototyping solutions, Stratasys. The industrial revolution is now led by 3D printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time-to-market and functionally test prototypes cheaper, faster and easier. Bruce Bradshaw, Director of Marketing in North America, will explore the large product offering and variety of materials that will help CAD designers articulate their product design with actual, physical prototypes. This broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3D printing. 3D Printing is
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
6 
