New Teijin president
Toho Tenax Co Ltd, the core company of the Teijin Group’s carbon fibers and composites business, announced that Teijin's board of directors has elected Shukei Inui, currently director and member of the board of Toho Tenax, as its next president. Inui will assume his new role on 1 April.
Akio Nakaishi, the current president of the company, will assume the post of general manager, composites business unit of Teijin Limited, on the same day.
This story uses material from Teijin, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
CCAI welcoming scholarship applications
The Chemical Coaters Association International (CCAI) is now accepting applications for its 2017 Matt Heuertz Scholarship Program. The primary objective of this program is to encourage advanced education in finishing technologies.
The scholarship program is maintained by the National CCAI and donations from CCAI Chapters.
Applications will be reviewed by the National CCAI Education Committee for the National Scholarship Program and will also be sent on to chapters that provide additional scholarship funding for students in their area. Award amounts vary and are determined by the National Office. Scholarship recipients will also receive a free one-year student membership in CCAI.
To view the criteria, selection process and to apply online, visit www.ccaiweb.com, click on the EDUCATION tab, and then scroll down to Scholarship Program. Students must complete a CCAI National scholarship application and provide a transcript or other grade verification and a resume with photo. The application deadline is 3 April 2017.
This story uses material from the CCAI, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
New dust information seminar launched
Dark Matter Composites and Composites UK are teaming up to provide a seminar on risks, generation, capture and control measures for both carbon and glass fiber dust.
The event takes place on 25th April 2017 at Dark Matter Composites’ facility in Redbourn, Hertfordshire, and builds upon the growing information contained in the Composites UK online Health and Safety Management System, which can be found here.
In 2016, 20 companies attended these events. Philip Spinks, CEO of Oxford Advanced Surfaces, who was one of the delegates said; ‘The main issue with dust control I’ve found is managing your process correctly to minimise its impact and the cost it incurs to deal with what’s left. I very much enjoyed the course, it was concise and got the key points across well.’
Registration for the event is now open via the Composites UK website (discounts available for members).
This story uses material from Composites UK, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
New study explains magnetic attraction of Mott insulators
Researchers at Brown University have shown experimentally how a unique form of magnetism arises in an odd class of materials called Mott insulators. Their findings could lead to a better understanding of the quantum states of these materials, which have generated much interest among scientists in recent years.
The study, published in Nature Communications, helps to confirm novel theoretical work attempting to explain how electrons behave in these strange materials. The work was done in collaboration with scientists at Stanford University and the US National High Magnetic Field Laboratory.
"We found that the theory holds up well," said Vesna Mitrovic, an associate professor of physics at Brown who led the work. "It shows that this new theory, based on quantum models involving complicated electron spin interactions, is a good start to understanding magnetism in strongly interacting materials."
Mott insulators are materials that should be conductors according to traditional theories of electrical conductivity, but act as insulators nonetheless. The insulating state arises because electrons in these materials are strongly correlated and repel each other. That dynamic creates a kind of electron traffic jam, preventing the particles from flowing to form a current.
Scientists are hopeful they can find ways of moving these materials in and out of the Mott insulating state, which would be useful for developing new kinds of functional devices. In previous studies, scientists have also shown that introducing impurities into Mott insulators can turn them into high-temperature superconductors – materials that conduct electricity without resistance at temperatures well above those normally required for superconductivity.
Despite the promise of these materials, scientists still don't fully understand how they work, because a full description of electron states in Mott insulators has proved elusive. On the most fundamental level, each individual electron is characterized by its charge and spin, its tiny magnetic moment that points either up or down. Predicting electron properties in Mott insulators is difficult, however, because the states of the electrons are so closely correlated with each other – the state of one electron influences the states of its neighbors.
To further complicate matters, many Mott insulators exhibit what is known as spin-orbit coupling, meaning that each electron's spin changes as it orbits an atomic nucleus. Spin-orbit coupling implies that the magnetic moment of an electron is affected by this orbiting, preventing the spin of an electron from being well defined. As a consequence, predicting the properties of these materials requires knowledge of interactions between the electrons, while the fundamental properties of individual electrons depend on their orbital motion.
"When you have these complex interactions plus spin-order coupling, it becomes an incredibly complicated situation to describe theoretically," Mitrovic said. "Yet we need such fundamental quantum theory to be able to predict novel quantum properties of complex materials and harness them."
Mitrovic's study focused on a strange type of magnetism that arises when Mott insulators with strong spin-orbit coupling are cooled below a critical temperature, causing alignments between the electron spins. But because the spins are strongly interacting and their values depend on orbital motion, it's not understood how this produces the observed magnetism.
There has been one important theoretical attempt to explain what might be happening in these materials on the most fundamental level to bring on this magnetic state. And that's what Mitrovic and her colleagues wanted to test.
To do this, Mitrovic's colleagues at Stanford University started by synthesizing and thermodynamically characterizing a Mott insulating material made of barium, sodium, osmium and oxygen, which Mitrovic probed with nuclear magnetic resonance. The particular technique the team used allowed them to gather information at the same time about both the distribution of electron charges and electron spin in the material.
This work showed that as the material is cooled, changes in the distribution of electron charges cause distortions in the material's atomic orbitals and lattice. As the temperature cools further, this distortion drives the magnetism by aligning the electron spins within individual layers of the atomic lattice.
"We were able to determine the exact nature of the orbital charge distortions that precedes the magnetism, as well as the exact spin alignment in this exotic magnetic state." Mitrovic said. "In one layer you have spins aligned in one direction, and then in the layers above and below it the spins are aligned in the different direction. That results in weak magnetism over all, despite the strong magnetism within each layer."
The theory Mitrovic was investigating predicted exactly this layered magnetism preceded by distortions of charge. As such, the findings help to confirm that the theory is on the right track.
This work is an important step towards understanding and manipulating the properties of this interesting class of materials for real-world applications, Mitrovic says. In particular, materials with spin-order coupling are promising for the development of electronic devices that consume less power than ordinary devices.
"If we want to start using these materials in devices, we need to understand how they work fundamentally," Mitrovic said. "That way we can tune their properties for what we want them to do. By validating some of the theoretical work on Mott insulators with strong spin-orbit coupling, this work is an important step toward a better understanding."
In a larger sense, the work is a step toward a more comprehensive quantum theory of magnetism. "Even though magnetism is the longest known quantum phenomena, discovered by the ancient Greeks, a fundamental quantum theory of magnetism remains elusive," Mitrovic said. "We designed our work to test a novel theory that attempts to explain how magnetism arises in exotic materials."
This story is adapted from material from Brown University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Searching for topological states in tungsten ditelluride
Researchers at the University of Pennsylvania have become among the first to produce a single, three-atom-thick layer of a unique two-dimensional (2D) material called tungsten ditelluride. This should now allow scientists to test whether, as predicted, tungsten ditelluride has topological electronic states, meaning it can possess many different electronic properties rather than just one. The researchers report their findings in a paper in 2-D Materials.
Graphene is the best-known example of a 2D material, comprising a one-atom thick sheet of carbon with many potentially useful properties. These include being a zero bandgap semiconductor, able to behave as both a metal and a semiconductor.
But other 2D materials can have many other properties. Some can be insulating, others can emit light and still others can be spintronic, meaning they possess magnetic properties.
"Graphene is just graphene," said A.T. Charlie Johnson, a physics professor at the University of Pennsylvania. "It just does what graphene does. If you want to have functioning systems that are based on 2D materials, then you want 2D materials that have all of the different physical properties that we know about."
The ability of 2D materials to possess topological electronic states is a phenomenon that was pioneered by Charles Kane, also a physics professor at the University of Pennsylvania. In this new research, Johnson, physics professor James Kikkawa, and graduate students Carl Naylor and William Parkin were able to produce and measure the properties of a single layer of tungsten ditelluride.
"Because tungsten ditelluride is three atoms thick, the atoms can be arranged in different ways," Johnson explained. "These three atoms can take on slightly different configurations with respect to each other. One configuration is predicted to give these topological properties."
"It's very much a Penn product," Johnson added. "We're collaborating with multiple other faculty members who investigate the material in their own ways, and we brought it all together to put a paper out there. Everybody comes along for the ride." These other members of the research team include: Marija Drndic, another professor of physics; Andrew Rappe, a professor of chemistry and a professor of materials science and engineering; and Robert Carpick, chair of the Department of Mechanical Engineering and Applied Mechanics.
The researchers produced tungsten ditelluride using a process called chemical vapor deposition. Using a hot-tube furnace, they heated a chip containing tungsten to the right temperature and then introduced a tellurium-based vapor.
"Through good fortune and finding exactly the right conditions, these elements will chemically react and combine to form a monolayer, or three-atom-thick regions of this material," Johnson said.
Although tungsten ditelluride degrades extremely rapidly in air, Naylor figured out ways to protect the material so that it could be studied before it was destroyed. One thing the researchers found is that the material grows as little rectangular crystallites, rather than the triangles seen with other materials.
"This reflects the rectangular symmetry in the material," Johnson said. "They have a different structure so they tend to grow in different shapes."
Although this research is still at an early stage and the researchers haven't yet been able to produce a continuous film of tungsten ditelluride, they hope to conduct experiments to confirm that it possesses the predicted topological electronic properties.
One of these properties is that any current traveling through tungsten ditelluride would only be carried at the edges; no current would flow through the center of the material. If researchers were able to produce single-layer-thick materials with this property, it could offer a way to route an electrical signal to different locations.
The ability of this material to have multiple properties could also have implications in quantum computing, which taps into the power of atoms and subatomic particles to perform calculations significantly faster than current computers. These 2D materials might allow for an intrinsically error-tolerant form of quantum computing called topologically-protected quantum computing, which requires both semiconducting and superconducting materials.
"With these 2D materials, you want to realize as many physical properties as possible," Johnson said. "Topological electronic states are interesting and they're new and so a lot of people have been trying to realize them in a 2D material. We created the material where these are predicted to occur, so in that sense we've moved towards this very big goal in the field."
This story is adapted from material from the University of Pennsylvania, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Move for Renishaw subsidiary
Renishaw Ibérica, 3D printing specialist Renishaw's subsidiary for the Spanish and Portuguese markets, has relocated to a new facility near Barcelona.
Located just outside Barcelona in the municipality of Gavà, the new facilities are located roughly 8 km from the international airport El Prat and will feature a new additive manufacturing (AM) lab with material development facilities and post-processing equipment for 3D printed metallic parts.
Renishaw Ibérica was formed in 1990 and now consists of over 30 people providing support throughout Spain and Portugal.
‘Our commitment to providing first class customer support to the Iberian markets is part of a wider strategy across the Renishaw Group for the continued investment in new product development, plant and equipment, and facilities,’ said Víctor Escobar, MD of Renishaw Ibérica.
This story uses material from Renishaw, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
Carpenter Technology to acquire AM specialist
Hardmetal specialist Carpenter Technology is to buy substantially all of the assets and business of Puris LLC, a producer of titanium powder for additive manufacturing (AM) and advanced technology applications, for U$35 million.
The assets and business to be acquired include Puris’ titanium powder operations and business, AM assets, patents and related intellectual property.
‘This acquisition will provide Carpenter with immediate entry into the rapidly expanding titanium powder market and is consistent with our strategic focus on strengthening our leadership position in important growth areas,’ said Tony Thene, Carpenter’s president & CEO.
‘The addition of titanium powder to Carpenter’s existing capabilities is significant due to the current and anticipated demand increases from the additive manufacturing industry, which produces mission critical parts supplied to aerospace and medical markets, as well as other markets,’ said Stephen Peskosky, vice president of corporate development at Carpenter.
As a result of the transaction, Carpenter will enter the titanium powder market significantly earlier than previously planned and will reduce its planned fiscal year 2017 capital expenditures by approximately US$20 million, the company said.
Puris’ existing site will operate as a functional unit of Carpenter Powder Products, complementing Carpenter’s existing broad portfolio of powder metallurgy offerings.
This story uses material from Carpenter, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
Keynote speaker announced for composites in construction show
JEC Group reports that Prof Mark Goulthorpe, associate professor at the Department of Architecture, MIT, will be the keynote speaker at the Future of Composites in Construction Show taking place in Chicago, USA, on 21 June 2017.
The new show is focused on end users in building and civil engineering, the third largest growing market for the US composites Industry.
Goulthorpe is currently Head of the new design stream in the master of science in architecture studies program and his current research centers on robotic fabrication and a variety of composite fabrication methodologies, as well as a new iteration of the dynamically reconfigurable HypoSurface.
‘Mark Goulthorpe’s vision makes him the perfect choice to support this endeavor and actively take part in substantially expanding and generalizing the use of composite materials in the building and infrastructure fields,’ said Nicolas Baudry, North America shows director at JEC. ‘The building industry is facing a productivity and affordability crisis in developed and developing markets, largely due to its inability to embrace new material-processing: over the past 30 years the building industry has decreased in productivity (despite a digital revolution) where the manufacturing sector has effectively doubled productivity. Evidently buildings face particular technical challenges, especially fire retardancy, adaptability and longevity; but many of these issues have nascent solutions developed in other sectors.
'However, there are no official industry leaders in the building industry to take a decisive first step; and the thought-leaders (architects and engineers) are caught in a project-by-project procurement logic that doesn’t suit sustained research and development drives. So, there is a profound need for the polymer industries to initiate comprehensive building-focused research to devise a range of emphatically-beneficial composite buildings, materials and methods that offer versatile, economical, code-compliant solutions.’
This story uses material from JEC, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
Mildred Dresselhaus, the “Queen of Carbon Science”, passes away
Mildred Dresselhaus, the pioneering scientist and engineer, has sadly passed away at the age of 86. Born in 1930 in Brooklyn and raised in the Bronx, Dresselhaus was the first female Institute Professor at MIT – where she focused mainly on graphite, graphite intercalation compounds, carbon nanotubes and low-dimensional thermoelectrics – and a significant figure in the development of nanoscience as a new field of energy research.
Her influential work on carbon began in 1963 with the publication of a key paper on graphite, and her further studies into the electronic structure of carbon were fundamental to establishing research into the electronic structure of carbon nanostructures and fullerenes. She worked unceasingly to explore the individual layers of carbon atoms and carbon fibers, demonstrating new carbon structures and providing the basis for the discovery of a 60-carbon structure that came to be known as the buckyball, while her research into fullerene led to the discovery of carbon nanotubes.
This work on nanomaterials also led her to being the first to exploit the thermoelectric effect at the nanoscale, showing how to efficiently harvest energy from the temperature differences in materials that conduct electricity. As MIT president Rafael Reif has said, “A physicist, materials scientist and electrical engineer, she was known as the ‘Queen of Carbon’ because her work paved the way for much of today's carbon-based nanotechnology”.
A physicist, materials scientist and electrical engineer, she was known as the Queen of Carbon because her work paved the way for much of today's carbon-based nanotechnologyMIT president Rafael Reif
Millie, as she was widely known, was on the MIT faculty for 50 years. Initially carrying out postgraduate study at the University of Cambridge and Harvard University, she received an MA from the latter and a PhD from the University of Chicago, where she studied under Enrico Fermi.
She was awarded the National Medal of Science in 1990 for her research into the electronic properties of materials, as well as for promoting opportunities for women in science and engineering. Millie also received the Presidential Medal of Freedom from President Obama in 2014 and was the first woman to win the National Medal of Science in Engineering. Her work was distinguished by many other awards, including the National Medal of Science and the Enrico Fermi Award, and she was the first solo recipient of a Kavli Prize for her contribution to the study of phonons, electron-phonon interactions, and thermal transport in nanostructures.
Millie carried out a number of important roles throughout her long career, including the director of the Office of Science at the US Department of Energy, chair of the governing board of the American Institute of Physics, president of the American Physical Society, president of the American Association for the Advancement of Science and treasurer of the National Academy of Sciences.
Readers are welcome to leave their own tributes and comments below.
Bacterial fuel cell papers over the cracks
Microbial fuel cells were first suggested before the First World War, but it is a technology that is yet to reach maturity more than a century later. However, researchers at The University of Rochester, New York, USA, believe that MFCs still hold great promise, perhaps for niche applications where conventional fuel cells or batteries are too risky to use. The researchers have now made such significant progress towards an efficient and viable MFC that they may well have found the niche that could take this field forwards.
Chemistry professor Kara Bren and postdoctoral fellow Peter Lamberg have developed a bioelectrochemical system that uses bacteria found in wastewater and an electrode made from paper coated with carbon paste. They use this proof-of-concept system to propose that carbon paste paper electrodes could be used to build a tenable MFC. Until now, the electrodes used in fuel cells running with wastewater have been made of metal which is prone to rapid corrosion, others have used carbon felt, which is less costly but becomes clogged up and ineffective. The Rochester team's solution was to simply replace the carbon felt with paper coated with a carbon paste, basically a mixture of graphite and mineral oil. This carbon paste-paper electrode is not only cheaper and easier to prepare but outperforms the carbon felt, the team reports. Indeed, "the paper electrode has more than twice the current density than the felt model," explains Bren. [Lamberg et al., ACS Energy Lett (2016), 1(5), 895-898; DOI: 10.1021/acsenergylett.6b00435]
The team built their electrode with a layered sandwich of paper, carbon paste, a conducting polymer, and a film of the bacteria. This is easily constructed but despite its simplicity has an output of 2.24 Amps per square meter. By comparison felt anodes in their system have a current density of just 0.94 Amps per square meter.
The carbon paste is essential to the functionality of the fuel cell because it can suck up the electrons released by bacterial metabolic action. In the present example, Bren used Shewanella oneidensis MR-1, a microbial species found in wastewater that can sequester toxic heavy metal ions and in so doing releases electrons. Once transferred to the carbon coating of the anode, those electrons will wend their way to the platinum cathode whereby a current flows as the electrochemical counter reaction occurs on the platinum surface.
"We've come up with an electrode that's simple, inexpensive, and more efficient," explains Lamberg. "As a result, it will be easy to modify it for further study and applications in the future."
Bren points out that the ease of preparation of these electrodes facilitates making different derivatives."We would like to test how different additives may enhance biofilm growth and longevity and extracellular electron transfer," she says. "In addition, we are interested in using systems like this to provide electrons to chemical reactions of interest." Ultimately, of course, the experiments were undertaken as a way to develop and test a cheap and easy to construct new anode material that could be used in MFCs.
David Bradley blogs at Sciencebase Science Blog and tweets @sciencebase, he is author of the popular science book "Deceived Wisdom".
Mapping nanoparticles atom by atom
Researchers have mapped the coordinates of more than 23 000 individual atoms in an iron-platinum nanoparticle to show the defects, the missing atoms, the substitutions and the deviations from the lattice. The work hints at what might be possible with high-resolution imaging but also feeds data into quantum mechanics models to reveal correlations between material defects and properties at the single-atom level. [Miao et al., Nature (2017) 542, 75-79; DOI: 10.1038/nature21042]
Jianwei (John) Miao of the University of California Los Angeles and his international colleagues explain the relevance of the new work: "No one has seen this kind of three-dimensional structural complexity with such detail before," he says. The focus of their work, an iron-platinum alloy with promise in the area of next-generation magnetic storage media and permanent magnet applications make it particularly poignant - defects mean disruption and data loss in storage media after all. The team reports in Nature that, "The experimentally measured coordinates and chemical species with 22 picometer precision can be used as direct input for density functional theory (DFT) calculations of material properties such as atomic spin and orbital magnetic moments and local magnetocrystalline anisotropy."
The team obtained multiple images of an iron-platinum nanoparticle using advanced electron microscopy at Lawrence Berkeley National Laboratory. They then applied a powerful reconstruction algorithm developed by the scientists at UCLA and known as GENFIRE for GENeralized Fourier Iterative Reconstruction - to build an accurate three-dimensional model of the thousands of atoms in this nanoparticle. "For the first time, we can see individual atoms and chemical composition in three dimensions. Everything we look at, it's new," Miao adds.
The study located more than 6,500 iron atoms and some 16,600 platinum atoms revealing them to lie in nine grains each containing different ratios of iron to platinum atoms. Atomic arrangements at the grain surface were more irregular than those closer to the center of the grain, Miao and his colleagues demonstrated. They also defined the grain boundaries, the interfaces between grains. "Understanding the three-dimensional structures of grain boundaries is a major challenge in materials science because they strongly influence the properties of materials," Miao adds. The calculations suggest that there are abrupt changes to magnetic properties at these grain boundaries in the iron-platinum nanoparticle.
The team hopes to use GENFIRE to analyze data from other materials in a similar way. With this tool, they hope to build a databank for materials that would be akin to the protein databank used by life scientists and others but with applications in materials science, engineering and beyond. "For our next step, we want to map out the 3D individual atoms at surfaces and interfaces, which play a very important role in material properties and functionality," Miao told Materials Today. He also suggests that the same method might itself be applied to biological and medical imaging that could be carried out with lower doses of radiation on sensitive objects.
David Bradley blogs at Sciencebase Science Blog and tweets @sciencebase, he is author of the popular science book "Deceived Wisdom".
PM factory on schedule
Additive manufacturing (AM) company Arcam AB says that a new powder metal (PM) factory run its powder manufacturing subsidiary AP&C in Montreal, Canada, is progressing well on plan.
With the new plant, AP&C will reportedly be the first dedicated AM material manufacturer to have multiple production sites.
‘The need for high end titanium powder is driven by the fast growth and adoption of additive manufacturing,’ said Magnus René, CEO of Arcam. ‘Arcam is determined to serve the industry through cost efficient solutions thus converting traditional manufacturing into additive manufacturing. A requisite is to offer highest quality powder for production at competitive cost and sufficient volumes. Recently AP&C received an order for 30 tons of powder for MIM applications, confirming the fast-growing need for titanium powder.
This story uses material from Arcam, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
Google invests in 3D printing
Desktop Metal, a start-up company specialising in metal 3D printing, says that it has raised a total of US$97 million in equity funding since its founding in October 2015, led by by GV (formerly Google Ventures).
The announcement comes as the result of a latest investment of US$45 million from GV as well as BMW i Ventures and Lowe’s Ventures. Desktop Metal says that will use the funding to continue to develop its technology and scale production as the company prepares for its product launch later this year.
Previous investors include NEA, Kleiner Perkins Caufield & Byers, Lux Capital, GE Ventures, Saudi Aramco, and 3D printing leader Stratasys.
‘Just as plastic 3D printing paved the way for rapid prototyping, metal 3D printing will make a profound impact on the way companies both prototype and mass produce parts across all major industries,’ said Ric Fulop, CEO and co-founder of Desktop Metal. ‘We are fortunate to have the backing of a leading group of strategic investors who support both our vision and our technology, and who are pivotal in propelling our company forward as we prepare for our product introduction in 2017.’
Fulop was the co-founder of A123 Systems and a general partner at North Bridge, an early investor in leading CAD and 3D printing companies, including MarkForged, OnShape, ProtoLabs and SolidWorks.
‘Advances in metal 3D printing are driving innovation across a wide range of automotive applications and we are excited to work with Desktop Metal as part of our vision in adopting additive manufacturing at BMW,’ said Uwe Higgen, managing partner of BMW i Ventures. ‘From rapid prototyping and printing exceptional quality parts for end-use production, to freedom of design and mass customization, Desktop Metal is shaping the way cars will be imagined, designed and manufactured.’
This story uses material from Desktop Metal, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
Pultruded panels win JEC award
Infrastructure project specialist Acciona Construcción SA says that it has won this year’s JEC Construction Innovation Award for its pultruded composite panels used as a leak-proof lining system in a Spanish high-speed railway tunnel construction project.
According to the company, there were limited retrofit solutions available to solve the water ingress problem in a section of the tunnel. Water resistant GRP composite panels proved to be the best solution since they were cost effective and a better long term alternative to the steel and concrete lining options considered. They also met subterranean fire standards.
Acciona used a total of 1,700 tonnes of filled Crestapol 1212 pultrusion resin and glass fiber reinforcement materials, supplied by Scott Bader, pultruding more than 15,000 composite panels which lined approximately 200,000 m2 of the tunnel walling and eliminated the water ingress problem.
This story uses material from Scott Bader, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
Metyx Composites exhibits new products at JEC
Metyx Composites plans to exhibit new fabric materials at JEC World composite show, taking place in Paris in March.
Metycoremax FS (Fire Shield) is a fire-retardant RTM reinforcement fabrics, compatible with all major resin types. Metycoremax FS is a halogen free, sandwich design, stitched glass fabrics with a fire retardant core. IIt will be produced at the Metyx plant in Istanbul, Turkey, available in the same published formats as Metycore RTM glass fabrics with additional glass layers, surface veils and biaxial skins are also part of the product range.
Another new product being promoted during JEC World 2017 is Metyx’s new range of ‘webbed’ carbon fiber woven fabrics. These new product additions to the Metyx product range for producing composite parts are suitable for the automotive, transportation, marine, rail, wind energy and industrial markets. The ’webbed’ fabric includes the addition of a fine layer of thermoplastic coating, which resembles a spider’s web, applied as a covering to the surface of the woven fabric. This addition can stabilize the woven fabric, making it less prone to deforming.
Also on show will be the company’s Metycore FS (Fire Shield), Eglass and aramid and carbon fiber technical textile products.
This story uses material from Metyx, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
New ceramic boasts highest ever contraction on heating
Researchers based at Nagoya University in Japan have discovered a ceramic material that contracts on heating by more than twice the previous record-holding material.
The machines and devices used in modern industry are often required to withstand harsh conditions. When the environmental temperature changes, the volume of the materials used to make these devices usually changes slightly, typically by less than 0.01%. Although this may seem like a trivial change, over time this thermal expansion can seriously degrade the performance of industrial systems and equipment.
Materials that contract on heating, or negative thermal expansion materials, are therefore of great interest to industrial engineers, as these materials can be mixed with normal materials that expand on heating. The aim is to produce a composite material with a desired thermal value, typically zero, which is maintained even at the extremely low operating temperatures used in cryogenic and aerospace engineering.
In a study published in Nature Communications, the researchers report a reduced ruthenate ceramic material, composed of calcium, ruthenium and oxygen (Ca2RuO4-y), that shrinks by a record-breaking 6.7% when heated. This is more than double the current record for a negative thermal expansion material, and the bulk material expands again when it is cooled. This discovery may lead to a new class of composite materials that could help improve the stability of device performance, prolong device lifetimes, and increase the accuracy of processes and measurements.
The size of the volume change, as well as the operating temperatures that trigger negative thermal expansion, can be controlled by changing the composition of the material. When the ruthenium atoms are partially replaced by iron atoms, the temperature window for negative thermal expansion gets much larger. This window extends to above 200°C for the iron-containing material, making it particularly promising for industrial use.
After noticing that the volume changes were triggered at the same temperature as caused the reduced ruthenate material to switch from a metallic to a non-metallic state, the researchers used X-ray techniques to investigate changes in the arrangement of the atoms. They saw dramatic changes on heating, with the internal atomic structure expanding in some directions but contracting in others.
Although the internal structure showed a net contraction, the crystallographic changes were not big enough to explain the giant volume changes in the bulk material. Instead, the researchers turned their attention to the material’s overall structure, and found empty voids around the ceramic grains.
“The non-uniform changes in the atomic structure seem to deform the microstructure of the material, which means that the voids collapse and the material shrinks,” explains corresponding author Koshi Takenaka. “This is a new way of achieving negative thermal expansion, and it will allow us to develop new materials to compensate for thermal expansion.”
This story is adapted from material from Nagoya University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Novel perovskite can extract energy from multiple sources
We are surrounded by many different forms of energy: sunlight, the heat in a room and even our own movements. All that energy – normally wasted – could potentially help power portable and wearable gadgets, from biometric sensors to smart watches. Now, researchers from the University of Oulu in Finland have found that a mineral with a perovskite crystal structure has the right properties to extract energy from multiple sources at the same time.
Many members of the perovskite family of minerals have shown promise for harvesting one or two types of energy at a time – but not simultaneously. One family member may be good for solar cells, with the right properties for efficiently converting solar energy into electricity. Meanwhile, another is adept at harnessing energy from changes in temperature or pressure, which can arise from motion, making them so-called pyroelectric and piezoelectric materials, respectively.
Sometimes, however, just one type of energy isn't enough. A given form of energy isn't always available – maybe it's cloudy or difficult to get up to move around, such as when driving. Other researchers have developed devices that can harness multiple forms of energy, but they require multiple materials, adding bulk to what's supposed to be a small and portable device.
In a paper in Applied Physics Letters, Yang Bai and his colleagues at the University of Oulu outline their study of a specific type of perovskite called KBNNO, which may be able to harness many forms of energy. Like all perovskites, KBNNO is a ferroelectric material, filled with tiny electric dipoles analogous to tiny compass needles in a magnet.
"This will push the development of the Internet of Things and smart cities, where power-consuming sensors and devices can be energy sustainable."Yang Bai, University of Oulu
When ferroelectric materials like KBNNO undergo changes in temperature, their dipoles misalign, which induces an electric current. Electric charge also accumulates according to the direction the dipoles point. Deforming the material causes certain regions to attract or repel charges, again generating a current.
Previous researchers have studied KBNNO's photovoltaic and general ferroelectric properties, but they did so at temperatures a couple of hundred degrees below freezing, and they didn't focus on properties related to temperature or pressure. This new study represents the first time anyone has evaluated all of these properties at once above room temperature, Bai said.
The experiments showed that while KBNNO is reasonably good at generating electricity from heat and pressure, it isn't quite as good as other perovskites. Perhaps the most promising finding, however, is that the researchers can modify the composition of KBNNO to improve its pyroelectric and piezoelectric properties. "It is possible that all these properties can be tuned to a maximum point," said Bai, who with his colleagues is already exploring such an improved material by preparing KBNNO with sodium.
Within the next year, Bai said, he hopes to build a prototype multi-energy-harvesting device. The fabrication process is straightforward, so commercialization could come in just a few years once researchers identify the best material. "This will push the development of the Internet of Things and smart cities, where power-consuming sensors and devices can be energy sustainable," he added.
This kind of material would likely supplement the batteries in electrical devices, improving energy efficiency and reducing how often they need to be recharged. One day, Bai said, multi-energy harvesting may mean electrical devices don’t need to be plugged into the mains electricity supply at all. Batteries for small devices may even become obsolete.
This story is adapted from material from the American Institute of Physics, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.
Reviewer Workshop with the Editors of MSEA @ TMS
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3A showcases new products at composites show
3A Composites plans to showcase its new AIREX T10.60 and BALTEKVBC QX products, based on PET foam and balsa composite materials, at the Paris JEC World show taking place in March.
AIREX T10.60, a new product in the AIREX T10 range, is a very low-density foam core with an homogeneous cell structure and cells which are oriented to maximize the vertical compression properties. According to the company, the shear properties in the sheets’ length direction exceed the values of all comparable products. AIREX T10.60 can be used in sandwich applications for applications such as trucks, nacelles, building and construction, among others.
‘3A CompositesAirexBaltekBanova participation at the JEC WORLD every year underscores our strong presence in the composite industry globally,’ said Eric Gauthier, president of global key accounts of 3A Composites Core Materials. ‘We are delighted to present AIREX T10.60 and BALTEK VBC QX at this important platform.’
This story is reprinted from material from 3A, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.