A comprehensive collection of news and information about composites.
Posted by: Ginger Gardiner21. May 2015
Two years ago, motorsports engineering company Prodrive (Banbury, UK) announced it had developed colored carbon fiber, after six months of research. Though it would not reveal any details, Prodrive showed off the images below, saying it could produce high-luster carbon fiber panels in almost any hue that are chip resistant, UV stable and highly consistent in both color and finish.
Motorauthority.com reported that Aston Martin, whose latest Vanquish model features a 100% carbon fiber body, would be interested. Indeed, the company’s unique personalization service, Q by Aston Martin, includes an option under SPORTING: “Cobalt Blue Carbon-Fibre is carried through to the facia, where the gradation runs from opaque to a clear weave at the base”; and another under MONTEREY 2013: “Jet Black Satin exterior is contrasted with gloss red tinted Carbon-Fibre trim.”
Motorsports firm Prodrive publicized its colored carbon fiber in April 2013 (left).
Q by Aston Martin features Cobalt Blue carbon fiber in its SPORTING option (center)
and red-tinted CF trim in its MONTEREY 2013 (right).
SOURCE: Motorauthority.com (left) and AstonMartin.com.
Though Prodrive has been quiet since 2013, another motorsports-based company, GPFone (Silverstone and London, UK) launched Hypetex in 2014, which it touts as the world’s first colored carbon fiber brand. Again, the technology evolved out of Formula 1 — this time after seven years of R&D — with details in short supply, but the company claims that Hypetex does not include filamentized glass fibers like some other products and thus maintains the essential high performance properties of carbon fiber.
Hypetex colored compound carbon fiber, reportedly developed by Formula 1 engineers, was showcased in designer Michael Sodeau’s Halo chair. SOURCE: GPFone.
Looking for a high-visibility way to introduce Hypetex, GPFone chose to work with London designer Michael Sodeau to produce the Halo chair, which features a thin wing-shaped seat on three legs and a disc-shaped back that gives a graphic silhouette. Hypetex reportedly enabled the structure to be thin and refined, yet robust. Winning the 2014 Red Dot Design Award for furniture, the Halo chair is reportedly available in six colors, with a limited production of six in each color.
As reported by Dezeen, Sodeau found that carbon fiber enabled him to generate shapes not possible with other materials and that Hypetex in particular offered a lot of design freedom: "It enables us to create a mono-material design, so aesthetically we can have a strong dynamic shape with one material over the whole object.”
Color via Other Fibers
Traditionally, colored carbon fabrics have achieved their rainbow hues via hybrid weaves with dyeable yarns such as glass, polyester and aramid. Vendors of these products are usually very straightforward about their products including caveats about the properties:
Please note that owing to the 50% coloured polyester yarn content of this fabric it does not have the same mechanical properties as 100% carbon fibre fabric, although it is still a high performance fabric.
— Easy Composites
This material is a blend of carbon fiber and colored copper wire.
— Composite Envisions
There are many carbon hybrid fabrics which use other fiber types to achieve color.
SOURCE: EasyComposites.co.uk (left), CompositeEnvisions.com.
Silver carbon fiber may actually be Texalium, a metal-coated glass fiber fabric from Hexcel (Stamford, CT). It is usually described exactly as this, though some less technical sources will call it silver carbon fiber while others explain that it is coated with aluminum approximately 200 angstroms in thickness. These latter sources will also describe post-treatment options which produce red, blue, yellow and other tints.
Soller Composites (Franklin, NH, US) has been selling its carbon and colored glass fiber hybrid fabrics for years, with adoptions in prosthetics, automotive aftermarket parts, fishing rods and other sporting goods.
Soller Composites sells a variety of colored glass/carbon fiber hybrid fabrics that are used in a variety of consumer goods. SOURCE: Soller Composites.
When not using Texalium or colored Kevlar, the artists of the automotive aftermarket suggest imparting color to normal carbon parts through paint. Specifically, color-matched paint can be mixed into a clear binder like DBC500 from PPG (Pittsburgh, PA, US) and then topped with clear coats as normal. Some experts advise simply spraying with candy paint, which is a three-stage system using a metallic reflective basecoat, candy color coat, and clearcoat to create a deep, colored luster not attainable with typical automotive paints. It’s not clear if they are omitting the metallic basecoat.
Alternative to using colored glass or aramid fiber (left), auto aftermarket parts may achieve colored carbon via translucent or candy paint systems. SOURCE: DeftRacing.com and Honda-tech.com.
If indeed ProDrive and Hypetex are not using other fibers to achieve color, perhaps they are using technology developed decades ago but never widely adopted. Sumitomo Chemical Company's (Tokyo, Japan) patent EP0420655 A2, awarded in 1991, which describes a colored prepreg featuring a “widely variable high-grade hue with depth and luster” which cannot be abraded or worn off. This is achieved by using a polymer resin with 5 to 50 parts by weight — preferably 10 to 30 parts by weight per 100 parts by weight of the synthetic resin — of a flaky colorant having an average particle size of 70 to 300 µm and an average thickness of 0.1 to 10 µm. Particles sized less than 70 µm lack sufficient luster while those beyond 300 µm lack adequate dispersibility. The low and high bounds on colorant amount are set for the same reasons. "Hiding pigments" are also included in the technology, which may partially cover the color of the reinforcing fibers. Possible flaky colorants and hiding pigments are detailed.
Apple, too, has patented a method for “updating” carbon fiber’s look. Patent US7790637 B2, applied for in October 2007, simply uses an additional “scrim” layer that can mask the carbon fibers and impart a color other than black. Not aimed at transparent color that maintains the visual weave, but instead targeted to improve the cosmetic surface finish, Apple’s patent is interesting mainly in its motivation:
“. . .the resulting carbon fiber composite can have cosmetic imperfections that reduce the aesthetic appearance of the molded article formed therefrom. Further, carbon fiber composites, often being black, provide a narrow range of surface appearance to the molded article and therefore may give a “tired”, unexciting look.”
Even though projected use of carbon fiber continues to soar, maybe “the new black” could stand some color options.
Posted by: Ginger Gardiner13. May 2015
LaminaHeat's PowerFilm and PowerFabric products can be integrated into composites enabling surfaces to be evenly heated up to 232°C. SOURCE: LaminaHeat.
Multifunctionality has become a mantra among aerospace OEMs and advanced manufacturing proponents. “Airbus needs more from the material than pure strength per kilogram,” explained Dr. Thomas Kruse, Airframe Design - Research & Technology at Airbus, in a 2013 presentation. The goal is to replace discrete functional layers (e.g. bronze mesh for lightning strike protection) with capabilities integrated into the composite materials, such as conductivity, vibration and acoustic damping, erosion resistance, structural health monitoring and de-icing. Composites offer real potential to achieve such multifunctional structures and are being developed for a wide range of applications.
LaminaHeat LLC (Greenville, SC) has demonstrated heated composite tooling and structures using its PowerFilm and PowerFabric materials. PowerFilm is a thin layer of carbon fiber (CF) insulated with a polymer and incorporating copper contacts that efficiently converts electricity into heat. Though only 100 microns thick, it can generate up to 10 KW/m2. This is roughly the same heat as 3 gas fires from 1 m2 of film, but converted with 99% efficiency vs. only 80% for gas flame, according to technology developer Peter Sajic.
The dense, homogeneous CF network used provides uniform heating via a lightweight, flexible and damage-resistant material. PowerFabric sandwiches this veil between woven fabrics for an expanded range of flexibility and applications. Temperatures up to 232°C can be maintained across large structures or localized in specific regions. A range of polymer and product finishing options allows manufacturers to laminate these products into composite structures.
Norco GRP Ltd. produced a multi-zone heated CFRP tool for curing 18m long wind blade tips using PowerFilm. SOURCE: Norco GRP Ltd.
Norco GRP Ltd. (Poole, Dorset, UK) has demonstrated the use of PowerFilm in an 18m long carbon fiber composite tool for Blade Dynamics’ (Southampton, UK) manufacture of tips for its 75m blades being tested in 6MW offshore wind turbines. Norco used ZPREG carbon/epoxy prepreg from Cytec Industrial Materials (Heanor, Derbyshire, UK) and PowerFilm to fabricate a multi-zone heated tool with external computer temperature control. Norco describes the tool as providing almost instant controllable heat exactly where it is needed. Norco has since used this technology for a number of other applications.
A variety of horseriding saddles now use carbon fiber composite trees — i.e., the frame around which the saddle is built. For example, WOW saddles use a patented “Y” shaped composite frame (left) and Pampa Saddles has a new carbon/Kevlar model.
SOURCE: WOW Saddles and Pampa Saddles.
A CF/polyethylene terephthalate (PET, or thermoplastic polyester) PowerFilm has been used recently in the world’s first fully adjustable saddle tree, enabling the structure to be heated and reformed to adapt to changes in the horse’s body shape without disassembling the saddle. A battery supplies current to the saddle tree, which is heated to PET’s softening point, after which a simple adjustable clamp is applied to conform the tree to the new shape. The process, which takes a maximum of ten minutes, can be performed while the saddle remains mounted on the horse and may save thousands of dollars per year. The technology is being heralded as revolutionary in the equestrian world.
PowerFilm is being used in the award-winning Barnsby i-Tree saddle, which can be easily and repeatedly adjusted. SOURCE: www.hay-net.co.uk and www.horsetalk.co.nz .
Citing work at the Massachusetts Institute of Technology (Cambridge, MA, US) and Battelle (Columbus, OH, US) to develop carbon nanotube-based systems for heating and curing composites and aircraft wing de-icing, respectively, LaminaHeat’s VP sales and marketing for North America Marc Anderson comments, “We already have a product that can do both of these.” LaminaHeat is working with a variety of aerospace manufacturers and research organizations to complete demonstrations of PowerFilm and PowerFabric for de-icing applications, and sees much broader applications.
Posted by: Jeff Sloan30. April 2015
The Hyundai Intrado hydrogen-powered crossover is a concept for now, but uses a carbon fiber passenger cell developed and manufactured by Axon Automotive.
Following the introduction of the carbon fiber-intensive BMW i3 and i8, the big question was, “What’s next?” Each automaker is taking a different tack in its composites integration, and there are some new signs of carbon fiber use in two new cars, one a concept and the other in production.
The concept car is the hydrogen-powered Hyundai Intrado crossover, introduced in 2014. It wasn’t until this year, however, that we learned more about the materials used to fabricate the vehicle’s passenger cell. Fabrication is provided by Axon Automotive (Wollaston, UK), which is well-known for its space-frame composite structures, manufactured using the company’s Axontex system. This employs braided tubes, which are infused to the desired cross-section shape over a low-density polyethylene (LDPE) foam core, which expands during infusion to provide compression against the mold.
The Axontex system for the Intrado uses Hyosung (Seoul, South Korea) Tansome H2550-12K high-strength carbon fiber vacuum infused with Scott Bader’s (Wollaston, UK) Crestapol 1250LV acrylic thermoset resin. The passenger cell also uses Scott Bader’s Crestabond adhesive to bond composite, aluminum and steel parts.
For vehicles, says Axon, its Axontex system allows structures to be optimized to place material where it is needed most. Further, the hollow components help save weight. Axon says it has developed and patented a high-volume manufacturing process for the production of Axontex parts and has been manufacturing passenger cells for Hyundai as the carmaker considers production plans. What’s unknown is when Hyundai might put the Intrado into production.
The 2016 BMW 7 Series uses carbon fiber supplied by SGL Automotive Carbon Fibers, which also manufactures material for the i3 and i8. The 7 Series is a hybrid of several materials, including composites, steel and aluminum.
The second vehicle, which is in production and will enter the market, actually comes from BMW. The 2016 7 Series, like the i3 and i8, uses carbon fiber supplied from SGL Automotive Carbon Fibers (SGL ACF, Moses Lake, WA) in a manufacturing process SGL calls Carbon Core. This appears to combine carbon fiber with other non-composite materials, including steel and aluminum. As a result, the new 7 Series is as much as 130 kg lighter than the 2015 version.
The 7 Series car will be at the 2015 International Motor Show in Frankfurt, Germany, Sept. 17-37.
Posted by: Jeff Sloan16. April 2015
ULA's Vulcan rocket, announced this week at the 31st Space Symposium, gives the US space program another option for putting people and equipment into space.
If you haven't been paying close attention to the space launch industry of late, you probably didn't know that it had been made quite complicated by Vladimir Putin. Indeed, the Russian leader's foreign policy antics in Ukraine, combined with some of his anti-United State rhetoric, has strained Russian-US relations, raising the spectre of the Cold War political struggles — even if only symbolically for now.
What's this have to do with space launches? For many years the United States has relied on Russia to supply its RD-180 rocket to power satellites and other craft into Earth orbit and beyond on the Atlas V launch vehicle. The R-180 is supplied by NPO Energomash (Khimki, Russia); the Atlas V is manufactured by United Launch Alliance (ULA, Denver, CO, US). However, as relations with Russia soured, this sole-source supply situaiton became, to put it mildly, unsustainable. It's been feared that if Russia were of the mind to do so, it could cease supply of the RD-180, leaving the US with no immediate alternative on hand. This has spurred the US government to call for US-made alternatives to the RD-180.
So, it was a big deal this week when ULA announced at the 31st Space Symposium in Colorado Springs, CO, that it is developing a new rocket, called Vulcan, designed to make "launch services more affordable and accessible," according to a ULA statement. ULA, the statement also notes, is responsible for more than 70% of the nation's space launches, so a new rocket source is critically important. In addition, ULA introduced with Vulcan the Sensible, Modular, Autonomous Return Technology (SMART) initiative, which will allow ULA to re-use the most expensive portion of the first stage — the booster main engines — via mid-air capture.
Neither is ULA alone in its rocket development. SpaceX (Hawthorne, CA, US) is working on a heavy-lift rocket, the Falcon Heavy, which will launch for the first time later this year. It has a payload of 117,000 lb, which makes it among the largest rockets ever made.
The upshot is that the US, finally, seems to have some rocket independence, which gives the American space program some much-needed space-access security.
Posted by: Heather Caliendo31. March 2015
Engel's concept for manufacturing a hybrid, brake pedal from thermoplastic fabric was on display at NPE2015.
Plastics recently saw its day in the sun during NPE2015 (March 23-27; Orlando, FL, US), the international plastics trade show that is held every three years. Some of the key players involved in thermoplastic composites exhibited a variety of solutions that are leading growth in new and emerging markets. Highlights included:
KraussMaffei demonstrated its FiberForm process that produced airbag housings made of fiberglass-reinforced polyamide with a shot weight of 350g in cycle times of 45 seconds. The FiberForm process developed by KraussMaffei combines injection molding with thermoforming of composite sheets to reportedly further improve the strength of fiber-reinforced plastics.
Lanxess presented a variety of exhibits featuring Durethan polyamides, Pocan polybutylene terephthalates (PBTs) and Tepex continuous fiber-reinforced composites in lightweight automotive applications. One key highlight was a hybrid design infotainment carrier made from a continuous fiber-reinforced polyamide composite and a polyamide 6 overmolding material that is being used for the first time in the Audi A6.
The American Composites Manufacturers Association (ACMA, Arlington, VA, US) sponsored the Composites Pavilion on the trade show floor as well as a half day of specialized technical education on the hot topic of thermoplastics to the Business of Plastics Track at NPE.
CW caught up with injection molding producer Engel during NPE to talk all things composites. In the next few years, the company foresees strong growth in the injection molding industry, particularly in the field of fiber composite engineering.
“Composites continue to become more and more popular,” Sebastian Picheta, who is responsible for Engel’s development of automation and handling solutions for composites, told CW. “There are so many new challenges to solve and that’s why we created our technology center.”
Engel established a technology center for lightweight composites in 2012 at the site of its machine production facility in St. Valentin, Austria. The technology center was created primarily as a platform for interdisciplinary collaboration with international partner enterprises and universities.
In fact, at NPE, Engel showcased one of the “milestones” that was achieved at the facility: a stress-resistant plastic brake pedal. The concept for manufacturing a hybrid brake pedal from thermoplastic fabric received the Composite Innovations Award in 2011, and has been consistently enhanced by Engel’s partner ZF-Friedrichshafen since then.
Using a vertical Engel insert 1050H/230 single injection molding machine with an Engel easix multi-axis industrial robot and infrared oven, a continuous-fiber-reinforced preconsolidated thermoplastic sheet was heated, preformed in a mold and immediately overmolded with polyamide. The system produces ready-to-fit components and no trimming is necessary, according to the company.
In addition, the product developers at ZF adapted the layer structure to the component load when designing the brake pedal. This enabled the component weight to be reduced by around 30% compared to conventional steel brake pedals—without impairing load-bearing capacity.
Engel says the control unit of the easix multi-axis robot is fully integrated into the control unit of the injection molding machine. As a result, besides making it easy to operate and program the robot, the movements of the machine and robot are coordinated with each other. Since the robot has access to the machine parameters, the gripper can enter the mold area during the opening movement, which in turn reportedly significantly reduces cycle times.
Automation is the key for composite materials to find even wider use in high-volume applications, such as in the automotive sector. Picheta said that at its technical center, the company is constantly looking at ways to develop manufacturing processes that produce high-volume parts but with low unit costs.
“Automation is not easy and new development is needed as there is more demand out there for mass production and to have fully automated cells,” Picheta said. “Automation will be a big part of the future.”