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Ukrainian engineer Vladimir Tatarenko showcased an idea for a detachable aircraft cabin he believes could save lives during a crash landing. In the event of a crash, the plane’s cabin would detach from the rest of the plane and safely land on the ground or water using parachutes, boosters and rubber tubes which would automatically inflate on water. The design also includes a storage space that holds passengers’ luggage underneath the cabin to ensure no luggage is lost in the event the plane needs to detach.
“Surviving a plane crash is possible,” said Tatarenko. “While aircraft engineers all over the world are trying to make planes safer, they can do nothing about the human factor.” I know this is his quote but maybe we can fix the grammar?
According to Tatarenko, a critical component to making the design work is the use of composites.
“The existing technology of using Kevlar and carbon composites for [the plane’s] fuselage, wings, flaps, spoilers, ailerons, tail will be used during the design,” said Tatarenko. “It allows to partly compensate the weight of parachute system.”
Last year, Tatarenko received patents for a similar invention with an escape capsule system that would rescue passengers on board. The capsule, just like the new one, would be released through a rear hatch at the tail end of the plane within seconds of an emergency situation.
However, the idea has plenty of critics. Some argue that the idea is not cost effective given how expensive the implementation of the technology would be to prevent a situation that is not common. Is it worth investing a lot of money in detachable technology if there were (according to Daily Mail) only 111 plane crashes in 2014? Others argue that the design itself still needs work, as it does not include a contingency plan for the pilots themselves.
A carbon and hemp-fiber reinforced component such as this is a cheaper, greener hybrid composite that can do the job of pure carbon composites.
Built in East Germany, the Trabant 601 was notorious for its many faults – not the least of which was a body made out of Duroplast, a hard plastic made of cotton waste and phenol resins that led those in the West to describe the car as being made of cardboard. However, it now looks as if the Trabant is getting the last laugh as scientists look at ways of making cars out of cotton and other botanical fibers formed into a new class of hybrid composites.
New emission, safety, and mileage standards in Europe and North America call for vehicles that are ever stronger and lighter, which means that steel and aluminum are giving way to carbon composite materials. Basically, such carbon fiber-reinforced plastics (CFRP) are made up of carbon fibers reinforced by resins, which provides strength and durability, and by tweaking the materials put in, engineers can alter the composite to fit particular applications.
These composites are light, strong, durable, and have proven their worth in everything from F1 racers to aircraft to surgical prostheses, but using them is a trade off. High-tech synthetic carbon composites may be marvelous materials, but they're also expensive and difficult to fabricate. Alternatives, such as glass fiber, can bring down the cost, but they tend to be heavier and not quite as strong.
The Application Center for Wood Fiber Research of the Fraunhofer Institute for Wood Research, the Wilhelm-Klauditz-Institut WKI in Braunschweig is looking into a more natural alternative to CFRPs in natural botanical fiber composites made out of flax, hemp, cotton, or wood. As the Trabant, with its Duroplast cotton composite, shows, the basic idea isn't new, but how Fraunhofer is applying it is.
The botanical composites don't seem like a very good choice at first. They aren't anywhere near as strong or durable as carbon composites, but they are as cheap as glass composites and lighter than glass. In addition, the botanicals burn cleanly without residues.
The clever bit is to take a bio-based textile and carbon fibers and combine them. The idea is not for the botanical fibers to replace carbon, but to supplement them. For example, the strength and durability of a composite panel doesn't need to be the same across the whole unit. Instead, carbon composites can be used in areas that are subject to high strength and wear, while the botanical composites cover other areas. Blending the two together therefore results in a cheaper, greener hybrid composite that can do the job of pure carbon composites.
Once explained, this hybrid composite seems fairly simple, but creating it isn't as straightforward. According to Fraunhofer, botanical fibers are usually made for use in textiles, which means they're treated so they'll run smoothly through spinners, looms, and other textile machines. However, composite engineers want fibers that are treated so they interact with the resins in a manner similar to roughening a wall so it will tightly grip the plaster. In the case of composites, properly treating the fibers can increase a material's durability by 50 percent. Such treatments are routine in carbon fibers, but Fraunhofer says that how to handle botanical fibers is still an unknown.
In addition to this, the Fraunhofer team is also studying how to manufacture the hybrid composites on an industrial scale, how to recycle them, and how to recover the materials in the panels.
Some of the carbon fiber shapes, created out of polyethylene using Oak Ridge's new technique
Thanks to research currently being conducted at the U.S. Department of Energy's Oak Ridge National Laboratory, our unwanted plastic bags may one day be recycled into carbon fiber. Not only that, but the properties of the fibers themselves could be fine-tuned, allowing different types of carbon fiber to be created for specific applications.
The Oak Ridge team, led by materials scientist Amit Naskar, start with polyethylene-base fibers – these could conceivably come from waste plastic sources, such as shopping bags and carpet backing scraps. Using a “a multi-component melt extrusion-based fiber spinning method,” the surface contours of these fibers can be customized, and their diameter can be manipulated with submicron precision. It is also possible to control their porosity.
Bundles of these fibers are dipped into a proprietary acid chemical bath. A process known as sulfonation causes the plastic molecules to bond with one another, transforming each bundle of fibers into one joined black fiber.
When subsequently exposed to very high temperatures, these fibers won’t melt. The heat does, however, cause many of their chemical components to turn to a gaseous state. After these have off-gassed, what’s left behind is a fiber composed mostly of carbon.
Many uses are envisioned for the plastic-derived carbon fiber – because of its tunable porosity, it may be particularly well-suited for applications such as filtration or energy harvesting. It is also hoped that the material could be used by the American auto industry, to make tough yet lightweight, inexpensive car parts.
Fiber reinforced composites are common, but do you know how to select the different types of fiber and resin used?
Comparing and Choosing Composite Materials
Composite materials are broadly defined as those in which a binder is reinforced with a strengthening material. Here we take a look at the pros and cons of the components: the resins and the fibers used to strengthen them.
Resins
Most modern composites share a common bond – almost literally. The binding resins – the chemical matrix in which the reinforcing fibers are embedded – are relatively few in number.
There are three main recipes: polyester, vinylester and epoxy. Various flavours of each are available, depending on whether they are strengthened with glass, carbon or aramid fibers, and the particular application. For example, high UV (sunlight) tolerance may be chemically engineered using additives.
Common Issues
The presence of volatile organic compounds(‘VOC’) is of concern both for health reasons and ‘greenhouse effect’ impact. Modern epoxies are VOC free, but polyester and vinylester compounds have high concentrations of VOC in the form of styrene. This means that fabrication using esters should take place in well ventilated space.
Curing
The epoxy compound is formed by mixing two different chemicals which react to form a ‘copolymer’. The curing rate is sensitive to temperature and the ratio of the two components, but curing is almost always assured. Some epoxy paste formulations will even cure underwater.
Polyester and vinylester by comparison, cure with the use of a peroxide catalyst (usually known as MEKP).
Vinylester is sensitive to temperature, and may not cure at all under certain conditions.
Water resistance
Epoxies are highly water resistant, with vinylesters also showing a high resistance.Polyester composites absorb water to a significant degree, and when used – say, in boat hulls – osmotic blistering occurs due to a reaction with water (hydrolysis) which results in chemical breakdown.
Insoluble pthallic acid crystals damage the GRP laminate and acetic acid is a by-product.
Chemical resistance
Epoxies are very stable chemically, and offer excellent resistance to chemical attack. Polyesters are moderately resistant at room temperatures to most common chemicals, but vinylesters offer much higher resistance, though falling short of the protection that epoxies afford. The resistance of polyesters and vinylesters falls quickly at higher temperatures. Vinylesters may be used to provide a barrier coating to protect polyester, particularly in the marine environment.
Shrinkage, Strength and Stiffness
Polyesters and vinylesters typically shrink by 7% on curing, but epoxies shrink less than 2% and where dimensional stability is important, then epoxies are much to be preferred.
Shrinkage can introduce stress into a structure, and designers much factor this in. Both for tensile strength and stiffness, polyester is lowest on the scale, with epoxy highest and vinylester just superior to polyester.
Adhesion
This is an important property when using composites. Adhesion has to be strong between the resin and the fiber strengthener. Vinylester is not the best in this respect.
Cost
Polyester is by far the cheapest of the three resin systems, much cheaper even than vinylester, weight for weight. Polyester is preferred for boats and bathtubs, but where strength/weight is important and budget less of an issue, then epoxies win – for example in motorsport and aerospace.
Fiber Types
There are three main families in use at present: glass fiber, carbon fiber and aramid fiber (more commonly known as Kevlar, a trademark of the DuPont Corporation).
Glass fiber is by far the cheapest and most widely used, and works well with all three resin types, but it is relatively heavy. Carbon fiber is much lighter, as are aramid fibers.
Glass fibers (either in chopped strand or woven cloth form) are most commonly used with a polyester resin, whereas carbon fiber, as a relatively high cost strengthener, is most usually combined with epoxy resins.
Adhesion
A resin has to ‘stick’ to the fiber strengthener, and it is important to select a resin/fiber combination (particularly with carbon and aramid fibers) so that there is good adhesion and the fibers are properly bonded within the resin.
Composite Comparisons
In general terms, Kevlar mechanical properties are good in strength (double that of glass fibers) but very poor in stiffness, whilst the glass composite is ten times as stiff and half the strength.
Kevlar is very expensive compared to glass, so it is used where higher strength and elongation is needed.
Both aramid composites and GRP are good at handling repeated flexing cycles (such as in a boat hull), but carbon fiber has an unpredictable life when subject to repeated flexing.
GRP requires a considerably ‘heavier’ construction to achieve the strength of carbon fiber. Aramid fibers offer equivalent strength to fiberglass at a much lower weight, although abrasion resistance is lower.
Summary
When choosing a composite, there are many factors to take into account. Many users of advanced composites – for example in the premium boat building industry – will combine all three composites to tailor engineering properties and weight distribution. In fact, we now have structures which are composites of composites.
Can the Lenovo Yoga 900S hit the sweet spot between power and portability?
CES 2016 is upon us, and one of the first Windows 10 laptops to be announced is the Lenovo Yoga 900S. With a carbon-fiber shell and a focus on lightness and long battery life, it's aimed at those looking for a computer that scores highly on portability without skimping too much on power.
As with Lenovo's previous Yogas, it features a folding screen you can flip all the way around so it's flush against the keyboard. The screen doesn't detach (as the one on the Surface Book does, for example) but you can use it as a tablet with the keyboard locked underneath. The previous Yoga 900 appeared three months ago, adding a lot more power for a little more heft, but the 900S heads back in the other direction.
The Yoga 900S felt both pleasantly light and thin in hand during our first brief encounter at CES this evening – and well it should, given that Lenovo is calling it the world's thinnest convertible laptop, with a thickness of 12.7 mm (0.5 inches) and a weight of 998 g (2.2 lbs). That means Lenovo's engineers have managed to shave off some 15 percent in thickness and around 11 percent in total weight compared with the original Yoga 900 we saw at the end of last year. The Yoga-like HP Spectre x360, in contrast, is 16 mm (0.63 inches) thick and weighs in at 1,440 g (3.17 lbs).
Then there's Lenovo's estimated battery life: 10.5 hours of local video playback (compared with 9 for the Yoga 900). We'll have to wait to get some quality time with the Yoga 900S to see if Lenovo's claims are on the mark, but the manufacturer is clearly touting long battery life as one of the key features of the convertible, and one of the reasons you might choose it over its predecessor.
Every laptop is a balance between power and portability and the Yoga 900S tips the scales towards the latter. It uses the new second-generation mobile Intel Core M7 processor rather than the i7 chips used in the Yoga 900, which should satisfy casual users but doesn't represent the very best laptop CPUs you can buy. Various configurations are going to be available, with up to 8 GB of RAM and 512 GB of SSD storage space available.
The laptop will be offered with a screen size of up to 12.5 inches at a resolution of 2,560 x 1,440 pixels (that's 221 pixels per inch). You get integrated Intel HD graphics, one USB 3.0 Type A port, one USB 3.0 Type C port with video out, and Windows 10 Home pre-installed. The familiar and rather stylish watchband hinge makes a reappearance too.
You can't produce the world's thinnest convertible laptop without making a few compromises with the internal components, but the specs of the Yoga 900S should cope fine with most daily tasks thanks to Intel's latest and most powerful mobile first chip. If it's caught your eye amongst the slew of laptops being announced at CES this year, the Yoga 900S goes on sale in March for a price of US$1,099 in either champagne gold or platinum silver.
Composites have emerged in recent years as a valuable class of engineering materials. They offer many attributes not attainable with other materials – they are lightweight, yet offer stiffness – and as a result can be found in a range of high tech applications such as satellites and high performance aircraft. Gel coats are used to provide a high-quality finish onto the visible surface of fibre-reinforced composite materials, which are then used in the manufacture of complex moulded parts.
This latest manufacturing breakthrough, achieved through the EU-funded ECOGEL CRONOS project, will therefore be of interest to mass production vehicle manufacturers, where even slight increases in efficiency and reductions in cost can lead to significant savings. The transport industry is also facing increasingly stringent environmental regulations which aim to increase the power-to-weight ratio of cars, reduce overall weight and thereby reduce vehicle emissions.
Composites have been identified as a key enabling technology that meets weight, cost and production rate requirements. The high tech aerospace sector, an industry that is characterised by high costs and low productivity, also stands to benefit. New manufacturing technologies that can achieve advanced aerospace materials at lower cost – and with less impact on the environment – will help ensure that Europe's aerospace industry has a strong future. Different manufacturing techniques were developed within the ECOGEL CRONOS project and combined with suitable additives in order to obtain highly reactive, stable and cost-effective powder gel coat formulations. The new process has been demonstrated to reduce both gelcoat manufacturing times and production emissions.
Project trials were carried out for composite parts used in tractors and car doors, and modelling tasks were employed to determine electrical conductivity thresholds. In a test run, a fully finished powder gel coat was delivered 80 % quicker compared to conventional liquid gel coats.
The three year project, which is scheduled for completion at the end of August 2016, is now focusing on developing new composite moulds for carbon fibre laminate. While traditional composites used in the automotive industry have typically used high cost aerospace-derived technology for a technique known as Sheet Moulding Compound (SMC), the ECOGEL CRONOS project is concentrating on Resin Transfer Moulding (RTM) to provide greater efficiency in terms of cost and production, with the same performance and quality.
The new RTM process, which involves reusable electrically conductive, temperature controlled skins, allows release agents, gel coats and fibres to be applied to the composite skin whilst another one is being injected. In this way it is possible to increase production for a relatively small additional investment. A pilot plant mould has been built and tests are currently being run.
Successful results could open the door to composite materials being used in other sectors, such as consumer, infrastructure and sporting goods industries. The transition to other mass-production sectors has to date been slow, in part because of the cost in manufacturing these materials, and the advances achieved through the ECOGEL CRONOS project could help address this challenge.
Read more at: http://phys.org/news/2015-12-composite-material-techniques-efficient.html#jCp
Composite production boards made of different types of pallets are playing critical roles in the furniture and other household requirements. The increased interest of modern man in composite production boards is caused as a result of its attractive properties like excellent vibration resistance, high mechanical stability, resistance against water, good wear resistance etc.
There are two types of Plastic Pallets for Concrete Blocks that are generally used for making composite production boards. They are generally known as Standard production boards and PRO production boards. Each side of The PRO production boards have semi-smooth surfaces on laminated fibre layers. These semi smooth surfaces give high wear resistance capacity to these boards. In the case of Standard production boards, resistible shuttering film is used to make the surfaces wear resistant. The stiffness of the production boards is increased and deflections of the boards are avoided as a result of fusion of these composite pallets for production boards. To avoid moisture absorption and the consequent delimitation, the saw cut sides of the Block Machine Plastic Pallets are Coated.
Composite pallets are made up of Hardwood fibres taken from Asian Plantation. Plantations along the South-East Asia are the location from where Asian Hardwood fibre is obtained. These composite pallets are made waterproof by treating it with a suitable waterproof resin. The composite pallets are made by pressing accompanied by heating processes which are carried out in fully automated and well calibrated machines. The ratio at which the Hardwood Faber and Industrial Grade Resin are mixed is decided after extensive research and experimentation. The Block Machine Plastic Pallets so produced are correctly machined according to the customer requirements in a more attractive manner with the help of specially designed machines so that the composite pallets look more attractive and technologically advanced.
ULLMAN, Wash. – Washington State University researchers have developed a catalyst that easily converts bio-based ethanol to a widely used industrial chemical, paving the way for more environmentally friendly, bio-based plastics and products.
The researchers have published a paper online describing the catalyst in the Journal of the American Chemical Society (http://pubs.acs.org/doi/abs/10.1021/jacs.5b07401) and have been granted a U.S. patent.
The chemical industry is interested in moving away from fossil fuels to bio-based products to reduce environmental impacts and to meet new regulations for sustainability, said Yong Wang, Voiland Distinguished Professor in the Gene and Linda Voiland School of Chemical Engineering and Bioengineering.
The industry has traditionally made a widely used chemical called isobutene – used in everything from plastic soda bottles to rubber tires – by superheating crude oil. But in collaboration with the Archer Daniels Midland (ADM) Company, Wang and his colleagues developed a catalyst to convert bio-based ethanol, which is made from corn or other biomass, to isobutene in one easy production step.
The researchers examined the costs and lifetime of their catalyst to determine its practicality for the marketplace and determined that it could be used for other closely related feedstocks. They also discovered just how their catalyst works, knowledge that could be used to design more efficient catalysts for a wide range of applications.
In addition to ADM, the work was supported by a grant from the Department of Energy (DE-AC05-RL01830, FWP-47319).
“This is one example that shows the benefits of closely linking the practical and fundamental aspects of research to develop scalable and commercially practical catalysts for applications of importance to industries,’’ said Wang, who holds a joint appointment in the U.S. Department of Energy’s Pacific Northwest National Laboratory (http://www.pnnl.gov/).
The guitar named ‘el capitan’ has been crafted from ekoa, a natural fibre composite made from flax linen and bio-resins. It’s currently the only guitar made using ecologically sourced composite materials and as rainforest wood becomes increasingly scarce could be the material of choice going forward.
Blackbird’s patented unibody construction and hollow neck developed over years of research and development allows the natural fibre guitar to be unaffected by temperature and humidity whilst also staying in tune much longer says the company.
Over the last 10 years, blackbird’s founder joe luttwak has focused on building non-wood acoustics to take on the road, that effort culminated in the development of ekoa as the first material designed to be better for instrument-making than wood.
With ekoa the company wanted to create a naturally derived material that for the first time offers a more dynamic range than the traditional rainforest wood as well as a better player’s experience with significantly stronger and more stable construction.
For the 30 megawatt (MW) Hywind Scotland Project, Siemens (Berlin and Munich) will supply five of its SWT-6.0-154 direct drive offshore wind turbines. The turbines will be installed on floating foundations operating in water depths between 90 and 120 meters. The world's largest floating wind project is located in Scottish waters 25 kilometers off the coast of Peterhead in Aberdeenshire. For the new Hywind Scotland Project, assembly in West Coast Norway is scheduled for first half 2017. In 2009, Statoil and Siemens successfully installed a 2.3 MW Siemens turbine at the first floating full-scale wind project worldwide, Hywind Demo.
The floating foundations are ballast-stabilized and fastened to the seabed with mooring lines. With their lightweight nacelles, Siemens large direct drive wind turbines are particularly suited for the floating foundations designed as slender cylinder structures. For the floating installation, Siemens’ technicians developed new controller settings for rotor pitch and yaw drive regulation.
“We are proud to once again be on board the floating wind project with Statoil, and to apply the experience we gained with the first full scale floating turbine,” said Morten Rasmussen, head of technology at Siemens Wind Power and Renewables Division. “Hywind Scotland is another pioneering project and has the potential to become a trailblazer for future floating wind projects.”
According to TRB Lightweight Structures (TRBLS), these major long-term benefits have driven leading manufacturers, such as Airbus and Boeing to design and build the latest commercial aircraft, such as the A380 and B787 Dreamliner, with over 50% of their structural parts made from fibrous composites. The composite system primarily specified for commercial aircraft is a honeycomb prepreg composite laminate produced in an autoclave, which is extensively used for interior applications including: sidewalls, ceiling and floor panels, galleys, toilets and partition walls; and also for exterior applications, such as: wing sections, flaps, ailerons, antenna radomes, access panels and doors.
TRBLS says that rail is poised to make the same sorts of gains in operating efficiency, performance and lifecycle cost benefits by using advanced technology composite materials for the next generation of high performance trains, which also need to be lighter, faster, more energy efficient and cheaper to maintain. To meet these new materials needs, TRBLS explains that it has added major new composites design and manufacturing facilities, certifications and people and is now able to help train manufacturers take advantage of the significant benefits in using advanced composites solutions.
TRBLS adds that it has been helping train manufacturers and operators for many years, with a long history as an IRIS-approved, Tier 1 supplier of lightweight engineering solutions for train builders worldwide. TRBLS claims it has designed, manufactured and sometimes installed components for projects as diverse as Hitachi’s new high-speed train, the London Victoria Line, and the UK West Coast Mainline to name just a few.
TRBLS says its design and materials processing capabilities now includes alternative lightweight composites materials that comply with the latest and most stringent fire, smoke and toxicity guidelines detailed in EN 45545. These materials include phenolic SMC (sheet moulding compounds), modified epoxy glass prepreg, fire retardant foam cores, carbon/phenolic prepreg, and select thermoplastic materials. The new 4000 sq. ft clean room, built to ISO 14644 standards, along with a newly installed autoclave (3m long x 1.5m wide) heated pressure vessel were key investments to meet the exacting needs of the Aerospace and Defence market: autoclaving is an established manufacturing processing step where only the highest quality composite structures are acceptable and is used extensively for making Aerospace approved components. TRBLS has also recently gained AS9100 (BS EN 9100) aerospace accreditation, a globally recognised quality standard for the aerospace and defence industry, adding to the IRIS (International Railway Industry Standard) and ISO 9001 certifications already in place.
Some recent high-profile Rail projects have begun to take advantage of more advanced lightweight materials and are reaping the benefits. Bombardier’s new AVENTRA platform - to substitute the Electrostar – weighs only around 30-35 tons, a decrease of up to 28% compared to earlier 42 tons designs: the new platform consumes 50% less electricity than the Class 319 equivalent and is faster, enabling quicker journey times. The new Siemens Desiro City platform is a modern, lightweight and energy efficient train, which is on average 25% lighter than current UK trains in service and consumes far less energy.
TRBLS explains that it has been working in partnership with rail customers to develop lightweight solutions in a wide variety of applications. Recent composites projects they have delivered include developing a new lightweight composite antenna cover for Alstom Transport, reverse engineering a stiffer and lighter coupler hatch for the West Coast Pendolino, and providing an innovative way to repair corrosion damage to sections of the castellated steel roofs on a fleet of train carriages; using a new TRBLS composite based patching system. TRBLS is also working confidentially with key OEM’s to design and build cost-effective composite solutions to remove significant weight from key components - up to 60% in some cases.
The new train roof composite repair system developed by TRBLS engineers, the company adds, has been approved by Virgin Trains in preference to using conventional welded mild steel patch repairs, which remain susceptible to corrosion and subsequent re-repair; polymeric composites materials inherently do not corrode. It is the first composite repair work of this type to be used for rail maintenance in the UK. According to revalidation engineering criteria, the composited patched roof section provides the same structural integrity as a welded steel patch.
The TRBLS says its composite roof repair sheet material is made from a glass fibre reinforced epoxy prepreg resin, which is first laid up in the clean room and then moulded at high temperature under pressure to aircraft specification quality standards in the autoclave. Standard 1m2 x 0.765mm thick sheets are produced, which can be cut to size as needed, allowing for the train roof design profile requirements. Roof repairs are made by bonding an epoxy glass patch over the damaged section using a rail approved structural adhesive certified to BS 6853 and BS 476 fire standards
This cost effective new roof repair system is designed to offer train operators significantly reduced maintenance costs, providing long lasting corrosion free repairs, and avoiding the need to replace the entire train roof at an estimated renewal cost of circa £100,000. Rolling stock is also out of service for less time; a TRBLS composite patch can be easily and quickly applied to repair a train roof within 24 hrs.
The TRBLS management team reports it has made major strategic investments to grow its capabilities while employing continuous improvement programmes across the business to increase efficiency, reduce costs, and raise quality even higher. Over the last four years, the business has expanded by approximately 10% annually, adding around 4,000sq.ft per annum of new factory space.
Speaking about the new strategy and business expansion, Richard Holland, Managing Director of TRBLS commented, “Over the last 18 months, in addition to putting in place our new composites capabilities, we’ve implemented improvements across the business. TRB Lightweight Structures is now, probably, one of the very few UK manufacturing companies with such a long history of supply to the rail industry, able to design from concept and deliver such a broad range of latest technology lightweight materials solutions. We are ready to take on and play a leading role in delivering the future needs of the rail industry.”
Elevators are one of those everyday machines that are uncommonly easy to take for granted, but whose function depends on a myriad of material and devices that go largely unseen — and must function flawlessly.
One of those unseen devices is the system of steel rope that attach to and ride with an elevator. They have worked dependably for many years, but have one flaw that makes them unusable in the super-tall buildings that dominate urban landscapes: They are too heavy.
Indeed, says Simon Barrette, communications manager at elevator manufacturer KONE (Espoo, Finland), current steel rope technology has reached its height limit: elevator travel distances of more than 500m are not feasible as the weight of the ropes themselves becomes so large that more ropes are needed to carry the ropes themselves. In short: Rope weight increases exponentially with building height.
A few years ago, KONE's customers started asking if there was a way to eliminate steel ropes in elevator design. This, says Barrette, "began our research into finding ways to reduce the weight of the ropes and we started looking at alternative materials. We benchmarked solutions from other industries and came across carbon fiber technology, which has already been used to reduce weight in industries such as aviation, automotive and the machine industry."
In 2013, KONE launched the KONE UltraRope, a belt-like elevator fabricated via pultrusion with carbon fiber, with a polyurethane coating. Barrette says KONE UltraRope was patented in 2008 and research of the application properties including thorough testing was conducted for seven years. According to the KONE patent for UltraRope, the belt-like rope is wider than it is thick, features a series of V-shaped longitudinal grooves, and can be pultruded with epoxy, polyester, phenoic or vinyl ester resins. The rope was tested at KONE's Hyvinkää reliability lab and testing towers, as well as at the Tytyri high-rise testing facility. Focus areas have been lifetime, environmental effects, temperature behaviors and friction properties in applicable conditions.
The result? KONE UltraRope will reduce the total cost of ownership thanks to significant reduction of energy consumption, reduction of downtime caused by building sway and the longer lifetime (2X) of ropes themselves, compared to steel. For an elevator with a travel height of 500m, energy savings would be approximately 30%. For an elevator with a travel height of 800m, energy savings would be as much as 45%.
Carbon fiber also offers an ancillary benefit as well, says Barrette. "In strong winds buildings start to sway, which also causes ropes to sway," he says. "At certain elevator positions rope resonance cannot be totally eliminated and for safety reasons elevator speed needs to be reduced or the elevators need to be completely stopped. KONE UltraRope resonates at a higher frequency than steel and most other building materials, meaning it is less likely to start resonating in high winds and this problem is minimized. Typically, building sway for very tall buildings is measured in tens of centimeters; in extreme cases, the sway can be more." The first elevator hoisted with KONE UltraRope was installed in one of Marina Bay Sands resort’s elevators in Singapore in September 2013. The Kingdom Tower Jeddah (Jeddah, Saudi Arabia), the world’s future tallest building (1 km high) once completed at the end of 2018, will feature KONE UltraRope technology and the fastest and longest DoubleDeck elevators in the world.
Further to the announcement made on 10 August 2015, Meggitt confirms that the acquisition of the advanced composites businesses of Cobham plc (Cobham Advanced Composites Limited, Compass Composites Products Inc and certain assets of Cobham Advanced Electronic Solutions Inc) for $US 200 million in cash has now received all necessary approvals and the transaction has been completed.
The acquired businesses will be integrated into Meggitt's polymers and composites division.
About the advanced composites businesses of Cobham plc:
The advanced composites businesses of Cobham plc comprise Cobham Advanced Composites Limited, Compass Composite Products Inc and certain assets of Cobham Advanced Electronic Solutions Inc. With a combined workforce of over 480 employees across four facilities in the US and the UK, the businesses are global leaders in the design, development and production of highly engineered aerospace composite engine components, radomes and structures. With over 30 years' advanced composite products experience, they have developed significant intellectual property and deep manufacturing know-how over decades and, through substantial investment, strong, established market positions.
Meggitt PLC:
Meggitt PLC is a leading international engineering group specialising in aerospace, defence and energy markets with a consistent record of strong financial performance. Meggitt's goal is to increase and strengthen its presence in long-term growth markets through proprietary product development reinforced by strategic acquisitions and investment in people and facilities. Meggitt's well-balanced portfolio offsets variation in demand from the market niches within which it operates.
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The research team have developed the first demonstration of 3D printing of composite materials. Image courtesy Matt Sutton, Tom Llewellyn-Jones and Bruce Drinkwater.
A team of engineers at the University of Bristol has developed a new type of 3D printing that can print composite materials.
According to the study, published in Smart Materials and Structures, the team has demonstrated a method by which ultrasonic waves are used to carefully position millions of tiny reinforcement fibers as part of the 3D printing process. The fibres are formed into a microscopic reinforcement framework that gives the material strength. This microstructure is then set in place using a focused laser beam, which locally cures the epoxy resin and then prints the object.
‘We have demonstrated that our ultrasonic system can be added cheaply to an off-the-shelf 3D printer, which then turns it into a composite printer,’ said Tom Llewellyn-Jones, a PhD student in advanced composites who developed the system.
In the study, a print speed of 20mm/s was achieved, which is similar to conventional additive layer techniques. The researchers have now shown the ability to assemble a plane of fibers into a reinforcement framework. The precise orientation of the fibers can be controlled by switching the ultrasonic standing wave pattern mid-print.
To achieve this, the research team mounted a switchable, focused laser module on the carriage of a standard three-axis 3D printing stage, above the new ultrasonic alignment apparatus.
New generation
This approach allows the realisation of complex fibrous architectures within a 3D printed object. The versatile nature of the ultrasonic manipulation technique also enables a wide range of particle materials, shapes and sizes to be assembled, leading to the creation of a new generation of fibrous reinforced composites that can be 3D printed, according to the team of engineers.
‘Our work has shown the first example of 3D printing with real-time control over the distribution of an internal microstructure and it demonstrates the potential to produce rapid prototypes with complex microstructural arrangements,’ noted Bruce Drinkwater, Professor of Ultrasonics in the Department of Mechanical Engineering. ‘This orientation control gives us the ability to produce printed parts with tailored material properties, all without compromising the printing.’
‘As well as offering reinforcement and improved strength, our method will be useful for a range of smart materials applications, such as printing resin-filled capsules for self-healing materials or piezoelectric particles for energy harvesting,’ added Dr Richard Trask, Reader in Multifunctional Materials in the Department of Aerospace Engineering.
Market research suggests that the glass fiber and special chemical fiber sector will grow annually by 6.47% from 2015 to 2020. Hyun-Dai Fiber.Co.Ltd. have been using their expertise and technical know-how to manufacture and supply various fibers - from superfine glass fiber to carbon fiber - in order to meet the demands of its customers.
(Photo: Business Wire)
Hyun-Dai Fiber.Co.Ltd is a well-established name in the composite materials sector, achieving mutual growth with customers and collaborating companies. This is based on the technology they use in the composite materials industry and long-time accumulated experiences.
Glass fiber is a popular option for use in composite materials as a reinforced element due to its heat-resistance, high tensile strength, weather resistance, electric insulation, and dimensional stability. The products are sold after being coated with suitable resin to match the purpose, e.g golf shaft, pipes, protective clothing, fishing rods, reinforced materials for wall, and insulation.
Carbon fiber possesses high elasticity, high heat resistance, and high strength. It exhibits superior functionality and property as an element for composite materials. By impregnating epoxy resin into carbon fiber textile, carbon fiber can be manufactured as prepreg state. The fiber is used widely in the aerospace sector, as it weighs less than plastic but is stronger than steel. The fiber can also be adapted to reinforce materials for industry and construction, and in sports and leisure, especially golf and skiing.
HD Fiber is directly manufacturing and supplying fabric sheet which can be used for body or parts in auto, sports/leisure or bicycle by using glass fiber or carbon fiber. In case of carbon fiber, we will advance into the market by making splendid and various fiber pattern rather than focusing on lightweight and strength.
A research team has developed a carbon-fiber manufacturing method that uses half the energy consumed in the current process and could increase maximum output of the strong but lightweight material tenfold.
The new process was announced on Jan. 14 by New Energy and Industrial Technology Development Organization (NEDO), which worked with the University of Tokyo, Toray Industries Inc., Teijin Ltd. and others in the development.
The production process of carbon fiber has remained nearly unchanged since 1959, when the current method was conceived by Japanese researchers.
Carbon fiber is now considered indispensable for reducing the weight of aircraft and automobiles.
Typical carbon fiber has about 10 times the tensile strength of iron but with only one-fourth of the weight.
However, the current carbon-fiber manufacturing method requires huge expenses and a large amount of energy to heat acrylic fibers at a high temperature for an extended period.
The new formula dispenses with the prolonged heating process by using specially processed chemical fibers.
Annual maximum output of carbon fiber is estimated at 2,000 tons per production line. The new process could bump up the amount to more than 20,000 tons a year, NEDO said.
Some industry experts expect the global carbon fiber market to grow 15 percent annually by 2020 as demand rises for production of aircraft and automobiles. The new process could further expand the market.
Three Japanese companies, Toray, Teijin and Mitsubishi Rayon Co., produce around 65 percent of the world’s carbon fiber.
Researchers tested the force required to pluck a boron nitride nanotube (BNNT) from a polymer by welding a cantilever to the nanotube and pulling. The experimental set-up is shown in a schematic on the left and an actual image on the right. Credit: Changhong Ke/State University of New York at Binghamton
Carbon nanotubes are legendary in their strength—at least 30 times stronger than bullet-stopping Kevlar by some estimates. When mixed with lightweight polymers such as plastics and epoxy resins, the tiny tubes reinforce the material, like the rebar in a block of concrete, promising lightweight and strong materials for airplanes, spaceships, cars and even sports equipment.
While such carbon nanotube-polymer nanocomposites have attracted enormous interest from the materials research community, a group of scientists now has evidence that a different nanotube—made from boron nitride—could offer even more strength per unit of weight. They publish their results in the journal Applied Physics Letters.
Boron nitride, like carbon, can form single-atom-thick sheets that are rolled into cylinders to create nanotubes. By themselves boron nitride nanotubes are almost as strong as carbon nanotubes, but their real advantage in a composite material comes from the way they stick strongly to the polymer.
"The weakest link in these nanocomposites is the interface between the polymer and the nanotubes," said Changhong Ke, an associate professor in the mechanical engineering department at the State University of New York at Binghamton. If you break a composite, the nanotubes left sticking out have clean surfaces, as opposed to having chunks of polymer still stuck to them. The clean break indicates that the connection between the tubes and the polymer fails, Ke noted.
Plucking Nanotubes
Ke and his colleagues devised a novel way to test the strength of the nanotube-polymer link. They sandwiched boron nitride nanotubes between two thin layers of polymer, with some of the nanotubes left sticking out. They selected only the tubes that were sticking straight out of the polymer, and then welded the nanotube to the tip of a tiny cantilever beam. The team applied a force on the beam and tugged increasingly harder on the nanotube until it was ripped free of the polymer.
The researchers found that the force required to pluck out a nanotube at first increased with the nanotube length, but then plateaued. The behavior is a sign that the connection between the nanotube and the polymer is failing through a crack that forms and then spreads, Ke said.
The researchers tested two forms of polymer: epoxy and poly(methyl methacrylate), or PMMA, which is the same material used for Plexiglas. They found that the epoxy-boron nitride nanotube interface was stronger than the PMMA-nanotube interface. They also found that both polymer-boron nitride nanotube binding strengths were higher than those reported for carbon nanotubes—35 percent higher for the PMMA interface and approximately 20 percent higher for the epoxy interface.
The Advantages of Boron Nitride Nanotubes
Boron nitride nanotubes likely bind more strongly to polymers because of the way the electrons are arranged in the molecules, Ke explained. In carbon nanotubes, all carbon atoms have equal charges in their nucleus, so the atoms share electrons equally. In boron nitride, the nitrogen atom has more protons than the boron atom, so it hogs more of the electrons in the bond. The unequal charge distribution leads to a stronger attraction between the boron nitride and the polymer molecules, as verified by molecular dynamics simulations performed by Ke's colleagues in Dr. Xianqiao Wang's group at the University of Georgia.
Boron nitride nanotubes also have additional advantages over carbon nanotubes, Ke said. They are more stable at high temperatures and they can better absorb neutron radiation, both advantageous properties in the extreme environment of outer space. In addition, boron nitride nanotubes are piezoelectric, which means they can generate an electric charge when stretched. This property means the material offers energy harvesting as well as sensing and actuation capabilities.
The main drawback to boron nitride nanotubes is the cost. Currently they sell for about $1,000 per gram, compared to the $10-20 per gram for carbon nanotubes, Ke said. He is optimistic that the price will come down, though, noting that carbon nanotubes were similarly expensive when they were first developed.
"I think boron nitride nanotubes are the future for making polymer composites for the aerospace industry," he said.
Local Motors is reinventing cars, and car-building, from the ground up, using 3D printing, carbon fiber, "Microfactories," and a wide range of customizable features.
Last year, when we saw the first example of a 3D-printed car from Local Motors, fellow TreeHugger Christine asked if this innovation could herald "a return to a more artisanal, small series form of manufacturing," and wondered if we can truly reduce waste with print-on-demand processes or if we will "find ourselves buried in a sea of layered plastic trash?"
While it's way too early in the development of 3D-printing for auto-making to know about the plastic waste issue, one thing is for sure: If Local Motors can fully scale up its processes to meet its audacious goal of having 100 "Microfactories" around the world in the next ten years, as well as a number of "Mobifactories" (mobile factories, naturally) for maintenance and sales of its vehicles, it may very well be the artisanal car manufacturer we've been waiting for. And perhaps it could spur on the more rapid adoption of electric vehicles at the same time.
Although Local Motors also makes a high-end rally car and a motorcycle, where the real rubber meets the road, at least as far as being a transformative car-maker goes, is in its LM3D series, which promises to be a truly different kind of vehicle. The LM3D, which is expected to be road-ready and safe (exceeding the Federal Motor Vehicle Safety Standards) when it becomes available sometime in 2017, includes a number of innovations that could be true game-changers for smaller-scale car manufacturing.
The LM3D is built with less than 50 individual parts (as opposed to the standard 30,000-plus parts in conventional vehicles), which equates to less tooling, fewer suppliers, and reduced waste in manufacturing, and according to the company, its Microfactories "produce a fraction of the emissions large automotive factories do," which adds to the elements of sustainability in Local Motors' operations. The current model of the car is built with 75% 3D-printed parts (made from a blend of carbon fiber and ABS plastic), with the aim of developing a vehicle that can be 90% 3D-printed. One distinguishing feature of the Local Motors' 3D-printed car series is the ability for replacement or custom parts to be printed directly at the company's microfactories, which can have a smaller environmental footprint than that of manufacturing in a traditional format, which requires an infrastructure set up with additional tooling and molding machinery. This on-demand parts manufacturing process could allow for a much easier way to replace damaged body parts, or to let owners upgrade their vehicles as needed, without the necessary stockpiling of parts and accessories that other car-makers rely on. And according to Springwise, the parts could be recycled "indefinitely," which means that buyers would only need to purchase a single car body "for a lifetime," with repairs or upgrades capable of keeping the original car up-to-date and on the road.
In addition to the safety and sustainability elements of the LM3D, the vehicle also includes a host of 'smart' features, both hardware and software, and is designed to be integrated with current and future Internet of Things (IoT) networks for a smarter and simpler way to get around. The company is also interested in getting input from the crowd through its Open IO innovation platform, where a number of ideas, tasks, and challenges to the project are being posted and feedback is welcome.
Find out more about Local Motors' LM3D series at its website, where you can also sign up to stay in the loop about its developments in preparation for a crowdfunding campaign, which is expected to launch sometime in the second quarter of 2016.
Unveiled back in 2012 in Beijing China as a super-sexy open-top version of the i8 plug-in hybrid sports car, the BMW i8 Spyder has everything it needs to become bedroom wall dreamcar material. It is sleek, agressive in its design, powerful and reasonably quick, taking around 4.4 seconds to hit 62 mph from standstill.
Powered by the same 1.5-litre three-cylinder turbocharged gasoline engine, 98 kilowatt electric motor and 7.2 kilowatt-hour lithium-ion battery pack as the production BMW i8, the BMW i8 Spyder Concept hinted what a summer-friendly version of the BMW i8 with removable hard top could look like. Designed by Richard Kim, (who now works at the enigmatic automotive startup Faraday Future,) the BMW i8 Spyder won the German automaker two different concept car awards — one in Beijing in 2012 and one in Geneva the following year — for its stunning design. Kim may have left BMW, but over the weekend we learned from German newspaper Handelsblatt (via BMWBlog) that the i8 Spyder has been approved for production, more than three years after it first debuted.
Talking to Handelsblatt, BMW CEO Harald Krüger said the BMW i8 Spyder is headed for production some point in the near future, boasting a potentially larger, more powerful battery pack and 2.0-litre, four-cylinder engine in place of the 3-cylinder 1.5-litre engine to increase overall performance.
Specifics are thin on the ground, but as our friends at Autobloggreen remind us, while BMW is happy to use fully-removable roof panels on concept versions of its open-topped vehicles, production vehicles tend towards automatically-retracting hard tops instead. Thanks to the extra space freed up by deleting the rear seats, the i8 Spyder should easily accommodate such a setup. While BMW has been working on the i8 Spyder for many years — initially with the hope of bringing it to market some time in 2015 as a 2016 model-year car — the ultra-lightweight carbon fiber reinforced plastic used across the BMW i-brand range has caused the German automaker some significant engineering challenges.
That’s because CFRP derives a lot of its intrinsic strength from the shapes it is moulded into, not just its mechanical composition. Try to make a CFRP cockpit with no roof, and there’s a lot less strength than there would be with a roof. Consequently we understand from 2013 that BMW’s engineers had to heavily modify the lower part of the i8 Spyder’s CFRP passenger cell to get the necessary rigidity needed for crash protection and body stiffness on the road.
Since then, we’ve heard little of the engineering challenge, but considering this new claim that the i8 Spyder is ready for production, we can only presume BMW has found a suitable solution. As to volume? While the BMW i8 proved incredibly popular when it launched last year, prompting massive dealer markups andwaiting lists more than a year long, we note that part of the demand was driven by clever marketing on BMW’s part — as well as a fairly modest production plan. Like its plans for the BMW i3 and BMW i3 REx electric cars, BMW’s initial i8 rollout plan was extremely conservative, so much so that BMW has since increased production plans to keep up with demand multiple times.
As a high-spec variant of an already niche-market car, we’d expect the BMW i8 Spyder would be produced in even smaller volumes, at least until BMW had proved a market for it. And that means, we’d suggest, that you’ll need a rather large hunk of cash — in excess of $150,000, we’d guess — to buy one.
US air carriers consume tens of billions of gallons of fuel a year. Though their fuel consumption dropped 15% between 2000 and 2014, rising oil prices meant that fuel costs increased more than 300% during that time. Even when oil prices drop, airlines still want to improve efficiency.
One way to increase fuel efficiency, and thus decrease fuel costs, is to increase the engine operating temperature. However, temperatures inside current aircraft turbines are already approaching the melting point of the metal superalloys used to make the engine components. These superalloys show surface softening at temperatures 15% below their melting point; normal materials, on the other hand, show surface softening at temperatures 30% below their melting temperature.
Engine makers like General Electric (GE) and Rolls-Royce are now replacing some metal parts in their aircraft turbines with ones made from ceramic-matrix composites (CMCs). CMC components can withstand higher temperatures than ones made from current superalloys. They are also about a third as dense as their metal counterparts, providing additional fuel savings by reducing weight, particularly for rotating parts.
A GE engine with a CMC component will appear on narrow body commercial aircraft starting in 2016. According to the company, this new engine uses 15% less fuel than its predecessor. Since aircraft turbines are structurally similar to land-based turbines that produce electricity, GE engineers hope to build CMC parts for other turbines too.
Ceramics researchers have dreamed of using CMCs in gas turbines for more than 40 years, said Krishan Luthra, chief scientist for manufacturing, chemical, and materials technologies at GE Global Research. Incremental improvements in metal superalloys have taken about three decades of research to increase turbine operating temperature from 950°C to around 1100°C today. With CMC components, engines can run at temperatures closer to 1300°C, gaining a 150°C increase in one step. “That’s why they’re revolutionary,” Luthra said.
Ceramics are typically brittle materials that shatter under stress. Fiber-reinforced CMCs, however, often fail like wood. When stressed, these materials first develop microcracks in the ceramic matrix, then they slowly bend, and eventually, they completely break. Woven fibers in CMCs bridge the microcracks and provide damage tolerance by hindering crack opening and further propagation.
Today’s best-performing CMCs are based on silicon-carbide (SiC) constituents. These SiC/SiC materials are typically made from nearly polycrystalline SiC fibers that are first covered with a boron nitride coating and then encased in a SiC matrix. To make the fibers, manufacturers cure and pyrolyze polymer precursors into long strands of SiC about 10–15 µm in diameter. Then they spin hundreds of these strands into rope-like tows. These tows are then woven into two-dimensional sheets, like thread is woven into fabric.
Next, individual fibers in the sheets are coated with an interphase material, commonly boron nitride. This coating is important for how CMCs behave under stress. The coating provides a weak interface between the fiber and the matrix so when matrix cracks reach this interface, they travel along and around the fibers, rather than through them.
Once coated, the sheets are stacked in a jig. The fibers in the sheets are aligned to provide maximum strength and stiffness according to the forces the material will experience during use. Materials under one-directional force are constructed so that the majority of their fibers are aligned parallel to that force, while CMCs under fairly uniform stress have fiber directions that alternate between parallel and perpendicular to the force.
Finally, the fiber stack is covered with a ceramic matrix. The components are introduced as gases, polymer solutions, liquid slurries, and/or molten silicon, and the SiC-based ceramic is formed under high temperature. Each processing method creates a material with different porosity. To minimize porosity and maximize performance, different sequences of methods are often used to create the matrix.
Pores reduce the amount of stress a material can handle before the matrix cracks. Under high temperatures, matrix cracks facilitate side reactions that weaken the CMC. Oxygen and water vapor travel through these cracks, attacking the fibers and their coating. These reactions can volatilize the coating and leave a residue that bonds fibers to the matrix or to each other. Oxygen also reacts with silicon or silicon carbide in the matrix, forming oxides on the CMC outer surface that volatilize upon reaction with water vapor produced during combustion. To prevent these detrimental side reactions, many CMCs are coated with an external oxide-based environmental barrier coating, often based on aluminosilicates.
After fabrication, a CMC is performance-tested to see if it can withstand the operating atmosphere, forces, temperatures, and pressures without cracking or delaminating. In turbines, the materials need to last for tens of thousands of hours and maintain their durability even if hit with flying debris.
Between 1997 and 2004, Solar Turbines, a California-based gas turbine manufacturer, tested SiC- and oxide-based CMC liners in the combustion chamber of their land-based turbines. Oxide-based CMCs contain alumina or mullite fibers in a matrix of alumina, silica, mullite, and/or rare-earth phosphates. They are more stable in oxidizing environments than SiC CMCs, making them better suited for the longer lifetimes needed in land-based turbines. But oxide CMCs offer little efficiency gains through temperature increase: they are stable at temperatures similar to current superalloys. After more than 67,000 hours of field tests, the company found that engines containing either type of CMC had lower emissions of carbon monoxide and nitrous oxides than the standard turbine.
GE also tested SiC-based CMC components in land-based electrical turbines, until market forces led them to focus on aviation applications, said Luthra, who has worked on CMCs for about 30 years. GE’s new LEAP engine contains a SiC-based CMC shroud that surrounds the turbine’s rotating blades. It will be featured first on Airbus A320neo planes and then, in 2017, on Boeing’s 737 Max.
Changing the composition of a stationary component also required redesigning the engine. Turbines with metal shrouds are designed so that air passes over the shroud to keep it cool. Since this air does not go through the turbine, it does not provide any extra propulsion. An engine with a CMC shroud, however, needs less cooling air. Redesigning the engine to reduce or eliminate the cooling air also increases its efficiency.
Lessons from using CMCs in aircraft engines will advance GE’s efforts to develop CMC components in electrical turbines, Luthra said. Because CMCs last longer than metal, the new components could reduce scheduled turbine maintenance that requires plants to completely shut down. And as with aircraft engines, CMC components could also provide the same improved efficiency and reduced emissions in electrical turbines.
Another frontier for CMC research is a push from National Aeronautics and Space Administration (NASA) scientists to increase the material’s temperature stability to near 1500°C. “Going to higher temperatures means better fibers, and we don’t have them yet,” said James DiCarlo, who has worked on CMCs at NASA Glenn Research Center for more than 35 years.
The goal is to develop fibers that resist creep, a deformation property that impacts the microstructure of the fiber, particularly at high temperatures. During creep, the fiber lengthens, grains in the polycrystalline fiber slide past each other, and holes appear between the grains. Those holes can eventually result in fracture of the fiber when a CMC is under stress. Creep also reduces a fiber’s ability to bridge growing matrix cracks.
To improve the fibers, NASA scientists are attempting to alter the microstructure of commercially available fibers by tailoring the grain size and atomic composition to reduce creep. The group is also working to improve CMC toughness by interlacing the fibers in three-dimensional patterns, so that some fibers wind up and down through the thickness of a stack of two-dimensional sheets. One challenge with this architecture is that the fibers rub against each other during weaving and can weaken from the abrasion. “There’s still research to be done: better fibers, better architectures, better ways of making fibers into those architectures, better matrix,” DiCarlo said.
CMC commercialization could help researchers improve the materials and develop them for other applications. Currently, CMCs are more expensive, and less predictable, in terms of performance, than metal superalloys. Only a few Japanese companies produce SiC fibers, in small amounts and with varying consistency. “The amount of fibers that GE needs to make all these parts will probably change everything,” said Gregory N. Morscher, at The University of Akron. Now that GE is optimizing their material and scaling up production to fill about 9600 orders for the LEAP engine, commercial fibers may have more consistent properties. “It’s still expensive, but things are getting cheaper and more reproducible.”
For CMC researchers and airline enthusiasts, the coming years will be exciting as more CMC turbine components appear on the market. Engineers at Boeing flight-tested an engine with a CMC nozzle in September 2014 as part of a federal program to improve aircraft fuel efficiency and reduce noise and emissions. In March 2015, GE ground-tested a commercial turbine with multiple CMC components. The GE9X, developed for the Boeing 777X and expected to be released in 2020, will have CMC nozzles, combustion liners, and turbine shrouds. The company is also developing a turbine for military aircraft that has rotating CMC turbine blades.
Triplicane (Tap) Parthasarathy, director of materials and processes at the research and development company UES Inc., Dayton, Ohio, USA, who has worked on CMCs for almost 30 years said, “It’s not often in a scientist’s career that something you work on will be used somewhere that benefits humanity at large.”
Reprinted from the Energy Quarterly section of MRS Bulletin.
High resolution SEM micrograph of entire Q-carbon film covered with microdiamonds (Credit: Jagdish (Jay) Narayan)
Carbon boasts the ability to exist in different forms and phases, and now researchers have discovered Q-carbon, a distinct new solid phase of carbon with the potential to make converting carbon into diamonds as easy as making toast (if you make toast with a high powered laser beam). It's early days yet, but researchers are already claiming that Q-carbon is magnetic, electro-conductive, glows in the dark, is relatively inexpensive to make and has stolen the crown of "world's hardest substance" from diamond.
Professor Jay Narayan of North Carolina State University is the lead author of three papers describing the work that sees Q-carbon join the growing list of carbon solids, a list that includes graphite, graphene, fullerene, amorphous carbon and diamond. He has suggested that the only place Q-carbon might be found in the natural world is in the core of certain planets.
The researchers created Q-carbon by starting with a thin plate of sapphire (other substrates, such as glass or a plastic polymer, will also work). Using a high-power laser beam, they coated the sapphire with amorphous carbon, a carbon form with no defined crystalline structure. They then hit the carbon with the laser again, raising its temperature to about 4,000 Kelvin, and then rapidly cooled, or quenched, the melted carbon. This stage of quenching is where "Q" in Q-carbon comes from.
Narayan says Q-carbon was discovered after a long search to find a mechanism for carbon to diamond conversion.
"This was the closure to a life-long effort, started when I first published a paper on the subject in 1979, followed by papers in 1991 and many others along the way," Narayan told Gizmag. "Finally, it happened."
This whole process of creating Q-carbon is relatively inexpensive. It's all done at room temperature and at ambient air pressure, using a laser much like the ones used for laser eye surgery.
So far, potential uses for Q-carbon are largely speculative, but Narayan says it might provide tools for industry and medicine, for electronic parts or for creating brighter, longer-lasting display technologies. But for now, there is one area where Q-carbon gets interesting (and by interesting I mean "potentially lucrative").
Diamond, being the world's hardest substance, has a range of uses in creating cutting and polishing tools across industries from mining to medicine. The challenge is that diamond is expensive to mine and to manufacture, requiring high temperatures and high pressures. But by mixing up the substrates and controlling the rate of cooling, Narayan and his team have discovered they can create tiny diamonds within the Q-carbon.
"It will take something in the order of 15 minutes to create one carat of diamond," Narayan told us. "But other applications will make a bigger impact."
Narayan says he envisages Q-carbon's first useful application will be in creating "a diamond factory for nanoproducts" for use in drug delivery and industrial processes.
"We can make Q-carbon films, and we're learning its properties, but we are still in the early stages of understanding how to manipulate it," Narayan says. "We know a lot about diamond, so we can make diamond nanodots and microneedles, [but] we don't yet know how to make Q-carbon nanodots or microneedles. That's something we're working on."
Volkswagen said Wednesday only about 36,000 vehicles could be affected in the carbon emissions matter, far fewer than originally feared. As a result, it no longer expects to have to set aside 2 billion euros ($2.18 billion) related to CO2 emissions.
CFM International's LEAP-1A commercial aicraft engine has been awarded Type Certification by the European Aviation Safety Agency (EASA) and the US Federal Aviation Adminstration (FAA). CFMnis the only engine manufacturer to gain dual original certification from both agencies, rather one lead agency issuing a type certification and the second agency validating that certification.
“It has been an incredible journey for the entire CFM Team to get the engine to this point,” says Francois Bastin, executive vice president of CFM International. “It is truly an achievement which involved our engineering, supply chain, and test teams, as well as EASA and the FAA. The LEAP engine includes many industry first technologies and the agencies have worked with us from the beginning to validate the certification plan for these advancements.”
The LEAP-1A flew for the first time on the Airbus A320neo on May 19, 2015. A second aircraft was added to the test program in September and, to date, the two airplanes have logged a combined total of more than 140 flights and 360 hours of flight testing.
“We are very pleased with the way all of the LEAP engine models have been performing during the test programs,” says Allen Paxson, executive vice president for CFM. “The LEAP-1A is doing extremely well in flight tests on the A320neo; the reliability we designed for this engine is definitely there. We are very confident that the LEAP engine family will deliver on every commitment we have made to our customers.”
The LEAP development and certification effort is the most extensive in CFM history. A total of 34 engines have been tested to date, logging more than 6,500 hours and 13,450 cycles. Test highlights include fan blade-out; bird ingestion tests, including medium, large, and flocking bird; ice slab ingestion; hail stone and hail storm ingestion; cross wind; icing; acoustics; emissions; triple-redline (maximum fan speed, maximum core speed, and maximum exhaust gas temperature) endurance test; and more than 700 hours of flight testing on modified 747 flying testbeds.
The LEAP-1A, which powers the Airbus A319neo, A320neo and the A321neo aircraft, features some of the industry’s most advanced technology, including 3-D woven carbon fiber composite fan blades and fan case; a unique debris rejection system; 4th-generation three dimensional aerodynamic designs; the Twin-Annular, Pre-Swirl (TAPS) combustor featuring additively manufactured fuel nozzles; ceramics matrix composite shrouds in the high-pressure turbine; and titanium aluminide (Ti-Al) blades in the low-pressure turbine.
The engine will provide operators with double-digit improvements in fuel consumption and CO2 emissions compared to today’s best CFM engine, along with dramatic reductions in engine noise and exhaust gaseous emissions.
Covestro explains that it has been a Solar Impulse project partner since 2010 and also its official technical partner. It was responsible for the design and construction of the Si2 cockpit which utilises the most advanced polyurethane and polycarbonate systems, significantly reducing the weight of the plane while ensuring ultimate protection for the pilot.
“To our employees and customers, the Solar Impulse project has become a symbol of Covestro’s innovation as well as our ability to provide a wide range of innovative solutions,” said Patrick Thomas, Covestro CEO. “We are delighted to be able to continue to support this inspirational endeavour as it embraces our corporate values of Curious, Courageous and Colourful.”
“Sustainability sits at the heart of our business strategy,” said Richard Northcote, Chief Sustainability Officer at Covestro. “This renewed commitment to Solar Impulse includes our role as one of the leading sponsors for the cross-America leg of the round the world journey, which will commence in Spring 2016. As more consumers seek energy-efficient products and governments start to implement the United Nation’s Sustainable Development Goals in legislation, Solar Impulse will play a huge role in showing the world how the technology that exists today can contribute to achieving what many believed was impossible.”
Covestro claims that technology developed for Solar Impulse is already used in various everyday products in the automotive and refrigeration sectors. In addition, coatings used on the plane are now also being used in many other industrial sectors.
Bertrand Piccard, Initiator, Chairman and Pilot of the Solar Impulse Project, said, “Thanks to our delay in the round the world adventure, Covestro will fly with us and demonstrate its essential contribution to Solar Impulse. All our partners share our vision of a cleaner future and the ongoing involvement of Patrick and the Covestro team confirms their commitment to achieving this aim.”
Andre Borschberg, Co-founder, CEO and Pilot of the Solar Impulse Project, added, “We have valued Covestro’s technical input, commitment and innovative spirit since 2010 and are looking forward to working even more closely with them over the next three years.”
He added, “I speak from personal experience when I say the cockpit Covestro designed for Si2, provided Bertrand and I with a comfortable and ambient environment to fly and work in. We are looking forward to getting back inside it for the next leg of the journey in 2016.”
Covestro explains that it is also supporting Solar Impulse’s ‘Future is Clean’ initiative, which is gathering global support for the use of clean energy, following the ratification of the United Nations Sustainable Development Goals and ahead of the Conference on Climate Change of the United Nations (COP21) this December.
Around 50 new jobs will be created. This is another step in the capacity expansions which BASF is undertaking because of the increasing demand for engineering plastics around the world. BASF’s global compounding capacity for PA and PBT will then be more than 700,000 metric tons per year. Already in the middle of this year, BASF in Shanghai more than doubled its compounding capacities for the two materials and also increased the capacities for thermoplastic polyurethane (TPU). In Korea a plant for compounding Ultramid and Ultradur started operations in October.
“With this expansion we strengthen our leading position in engineering plastics in Europe”, says Dr. Melanie Maas-Brunner, head of BASF’s Performance Materials Europe division. “By investing in highly efficient plants we help our customers to meet the increased demands on the materials, e.g. for large-volume and globally manufactured components in the automotive industry. As a reliable partner we thus support the growth of our customers and help them to overcome challenges such as lightweight construction and emission reduction with innovations.”
The engineering plastics Ultramid and Ultradur are processed into high-performance components in the automotive industry, the electrical and electronics sector as well as in the construction and furniture industries. Examples of such components are car seat structures, oil pans, engine mounts, sensors and connectors, chairs and fixings. The current innovations include the world’s first rear axle transmission cross beam in the Mercedes S-class, the Belleville design chair from Vitra, and also power semiconductor modules from the company Semikron.
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Ukrainian engineer Vladimir Tatarenko showcased an idea for a detachable aircraft cabin he believes could save lives during a crash landing.