For good reason, a lot of attention is given to the mainstream appplications of carbon and glass fiber reinforced plastics. However, from time-to-time it is benefitial to look ahead at some of the the up-and-coming trends. in advanced composites. In this blog we'll take a look at four current trends with some big potential.
1. Graphene Composites
Graphene has been on the list of world-changing super-materials for over a decade, but has yet to really take-off, largely due to the difficult and expensive extraction process.
Because of its excellent conductive properties, it could be a replacement for silicon chips in computers or for the top layer of touch screens (currently indium tin oxide which is both brittle and rare).But despite the price, the hype is understandable. It’s an amazing material, called by some the most useful material ever discovered, with many potential applications.
This enormous fanfare has everything to do with it’s not-so-enormous size. It conducts electricity better than silver, conducts heat better than diamond, and it’s stronger than steel. Further, it is so thin (typically 1-10 carbon chains thick) that is only absorbs about 2.7% of the light that passes through it (rendering it nearly invisible).
One company - Applied Graphene Materials – is looking into incorporating graphene into existing advanced comiposites to improve the strength or conductivity characteristics. The strong carbon–carbon bonds within a sheet of graphene open up the possibility for using either sheets of pure graphene in applications where the strength can be exploited directly or adding graphene to other materials to improve their mechanical strength. One such application of this approach is within a recent Head tennis raquet which incorporates bits of graphene to improve strength. However, inclination says this is just marketing hype.
Industry leaders believes that in order for grapehene to meet its expectations, we must create devices that rely on a combination of graphene’s properties — flexible electronics membranes that desalinate water. There are so many potential applications being thrown at the wall - one is bound to stick. [Photo from Nature.com]
2. Vertical Takeoff Drones (and rapid composite manufacturing)
Unmanned aerial vehicle or drones have become a hot topic in the media and are being used more and more to perform a wide range of military and civilian missions from reconnaissance, to delivering bombs, to delivering Amazon packages. Of the 200 (and counting) different varieties of unmanned vehicles, all of them contain at least one composite part. Glass and quartz fiber composites are regularly employed in sensor radomes, nose cones and small fairings. And due to mission requirements, carbon fiber composite parts are being examined as well.
One interesting sub-category of drones are the byte-sized vertical takeoff drones. These are the vehicles that, when regulations are loosened, will be delivering our food and mail, and checking the health of our livestock. Currently, government regulation on commercial use is artificially throttellling the market. However, while public airspace is currently restricted, the U.S. Government Accountability Office currently endorses the view that restrictions will be relaxed by the end of the decade.
One company that is making strides in the VTOL drone space is, aptly named, Rapid Composites. They are the makers of the award winning drone below that went from concept to prototype in just 3 months. It was initially designed to simply showcase the capabilities of the vertically integrated design and manufacturing shop, however recently the drone has taken-off on a life of its own.
"Rapid" is a jack-of-all-trades composite company specializes in the design of multifunctional composites that combine EMI/RMI Shielding, Thermal Conductivity, and Durability/Ruggedness, with extremely fast manufacturing times. Using their in-house developed processing techniques, every part on this drone can be manufactured in 11 minutes or less. Contrast that to typical hand-layup, autoclave processes that can take several hours. As these devices become more popular, time-to-production will be the name-of-the-game and Rapid Composites is poised to strike.
3. Natural Fibers
We spend a lot of time talking about the benefits of man-made fibers, but an emerging trend is to use renewable natural fibers as a reinforcement within plastic parts. The most popular of the natural fibers are the vegetable-based fibers like flax, hemp, jute, or kenaf. There are a number of obvious advantages to natural fiber. They are completely renewable, low weight, biodegradable, and relatively inexpensive. From a mechanical standpoint, they have a good strength-to-weight ratio and offer better dampenig ratio than standard frp's. For this reason they are commonly used in sporting equipment where vibration and stiffness is a major concern.
An interesting recent development is to incorporate the moderate use of natural fibres alongside traditional man-made fiber-reinforced plastics to create an ideal part. Take for instance, the power-rib technology of Switzerland-based Bcomp. They use natural fibers to provide reinforcement to existing homogeneous or composite structures. Their "Power-Ribs" are based on the concept of the leaf-veins, rigidifying a surface with minimum weight.
Another example is the JEC award winning flax-tap, which is a textile based fabric made of unidirectional flax fibers. This range of flax reinforcements have been developed to mainly enhance the vibration absorption qualities, mechanical properties, weight reduction and aesthetic aspect of composite parts. Below is a comparison of Flax Tape laminate composite vs. Eglass. Additional information on Flax-Tape and how it stacks up to traditional composites can be found here.
4. Shelby Cobra (and 3D printed composites)
This car has been featured before on this blog, but it’s certainly worth another look. It has the double-benfit of using two trendy technologies: 1. Short chopped fiber composites 2. 3d printing.
The car’s shell, support frame, monocoque, grille, headrest brackets are 3D-printed. The car was built in the Oak Ridge National Lab using the Big Area Additive Manufacturing (BAAM) machine, which can incorporate chopped fibers within a plastic filament..
The Shelby was printed using 20% carbon fiber reinforced ABS material and was only 6 weeks from conception to finished product. This is no-question an amazing feat. However, if this type of rapid production is going to make it to the next level, the inherent complexity of the fiber orientation, coupled with the 3d-printing-induced geometric non-linearities, need to be accounted for in the design and analysis phase. Read more about these Microstructural complexities here.
MultiMechanics loves to be a witness and participant in this material renaissance and has built our company to help support it. Because of MultiMech's unique and flexible microstructural modeling techniques, we can easily capture the behavior of all varieties of (very) advanced materials.
If you know of any other composite trends, let us know! We would love to take a look.