A new press release from Lux Research criticizes Boeing for not spec’ing a safer lithium-ion battery chemistry for its fleet of 787s, which have been in the news because of aircraft fires (Jan. 7 and Jan. 16) that press reports link to onboard batteries. The FAA also has grounded all 787s of US air carriers until safety concerns can be reviewed.
Lux says that Boeing selected a high-energy battery type—lithium cobalt oxide (LCO)—that has an inherently high risk of thermal runaway. While the exact cause and sequence of events that led to the fires are still being investigated, Cosmin Laslau, Lux Research Analyst, says, “Boeing made a design decision favoring higher energy over safer options, and is now paying the price.”
The research group also notes that another company paying a price is GS Yuasa, the Japanese company that makes the batteries in question. Lux says the company’s stock value dropped 5 percent in one day.
Lux is puzzled by Boeing’s decision to opt for LCO batteries. In its release, Lux says
In choosing LCO, Boeing eschewed safer alternatives such as lithium iron phosphate (LFP). Even when overcharged, LFP changes only slightly in structure, preventing oxygen release and resisting thermal runaway. This decision is all the more shocking considering major automakers early on refused to entertain the possibility of using LCO in passenger vehicles due to safety concerns.
The New York Times reports that not everyone is criticizing Boeing. A story today quotes Hans Weber, president of aviation consulting firm Tecop as saying, “you cannot do pioneering work without assuming some risk… In today’s world, we don’t have to pay the price of pioneering with death anymore, but we have to accept the fact we will have some incidents.”
NYT also interviewed Northeastern University chemistry professor Sanjeev Mukerjee, who suggests that there may be multiple problems in the 787s battery systems. He bluntly told the newspaper, “If a battery of that size catches fire, then a whole bunch of mechanisms didn’t work. Whoever is making that battery is doing a really bad job.”
The National Transportation Safety Board removed the Li-ion battery that powered the auxiliary power unit on the airplane involved in the Jan. 7 incident and sent it to the NTSB Materials Laboratory in Washington. NTSB investigators plan to disassemble it this week. The agency also says that in advance of that work, an independent test facility conducted radiographic examination of the incident battery and a pristine battery. These radiographs and CT scans will be used to document the internal condition of the battery prior to disassembling it. The NTSB also notes that its investigators took possession of burned wire bundles, the APU battery charger, and several memory modules.
It important to note that despite some reports, the Boeing/Yuasa batteries are not the same as those used in automobiles.
The AP has also posted the following video about the battery problems of the 787:
Background image: Molten glass. Credit: Michael Germann; Dreamstime.com.
Peter and I thought it would be fun to share our five favorite posts from 2012. Finding that choosing only five was nigh impossible, I decided to sort my picks into three categories, which instantly grew my budget to 15 stories!
Advances in science and engineering are subject to forces beyond physics, chemistry, and mathematics, such as politics, culture, history, and more.
USPTO issues flurry of new rules to implement ‘America Invents Act’
Archaic US patent rules were thrown out with adoption of the Leahy-Smith America Invents Act. New rules, though, mean changes in the strategy of innovation.
Data drives engineering of ceramics; workshop asks ‘how well?’
Computational approaches to materials engineering are only as good as the data they consume and digest. A DOD-sponsored workshop evaluated the state-of-affairs for electronic access to ceramic property data and the attendant challenges and opportunities.
Science research drives economic growth, but it’s expensive and slow
What role should governments take in investing in basic research, and how does a nation’s R&D investment impact GDP? There is nothing like an election year—in the US and abroad—to draw attention to what governments should spend money on versus what they do spend money on.
Video: Grand challenges in ceramic science—Preliminary findings from workshop
Researchers go bravely where others cannot or dare not. A group of the nation’s top ceramic science researchers convened to tease out the largest scientific challenges that can be addressed with ceramic materials.
Historic January 1987: YBCO superconductors discovered and Super Bowl XXI
This story about the discovery of high-temperature YBCO superconductors shows that research breakthroughs are often the progeny of systematic, well-executed fundamental research… and serendipity.
I’m an unabashed materials geek, and these were some of my favorite super-sciency stories—with the qualification that I mostly write about science that intrigues me, so this is a lot like choosing a favorite child.
Understanding the ‘between’ spaces: Interfacial phases and solid-state sintering
The formation and stability of interfacial phases in the solid state drives properties, so understanding how interfaces form and the thermodynamics driving them is of paramount importance.
Mullite-like mixed oxides may replace platinum for catalyzing diesel pollution
Manganese-oxide compounds with the mullite crystal structure may one day displace platinum as the catalyst agent in automobile catalytic converters.
High-alumina optical fibers get around Brillouin scattering limitations
Ever wonder how data gets to your smart phone or laptop so fast? A group of glass scientists is working on the next generation on optical fibers that will move more data, faster, and with more accuracy.
High critical current density doped pnictide superconductors
Harnessing the promise of high-temperature superconductivity requires a deep understanding of the physics of magnetism and the influences of composition and microstructure. Plus, what’s not to love about the word “pnictide?”
Heat transfer—two new studies look at effects of interface bonding, surface roughness
The digital age is generating some very sophisticated heat transfer challenges. How exactly does heat egress from a surface, and how can the mechanism be engineered?
Useful metrics for comparing new energy storage technologies
Measuring is an essential experimental activity. However, scientists and engineers must continually ask themselves the question, “Am I measuring something meaningful and useful?”
And this last group of five was just fun to write about.
Don’t wait in line for coffee: How to know where the business opportunity is
A reflection on business, opportunity, finding the way, and waiting in line.
Oldest known pottery dates back 20,000 years and may have changed the course of human history
The earliest ceramic engineers designed pots for cooking and brewing, proof that since time immemorial, engineers bring the life of the party. Literally.
Friday fun video—Gravity-defying Slinky
Adulthood does not mean toys become irrelevant. This video shows that scientists never stop learning the lessons that educational toys can teach.
Technical ceramics and art ceramics—only a brain apart
In the world of ceramics, is there a line between art and science? Yes, sort of—and no, not really. The American Ceramic Society serves the professional needs of engineers, scientists, studio artists, and hobbyists.
A castle vacation, poster session included
An October vacation to Germany included a conference at a Bavarian castle and the opportunity to talk shop with some of the best minds in the world working on biomineralization.
Were you counting? Me neither. Did you have a favorite story or topic that we covered? Let us know!
Best wishes for a Happy New Year!
What did our readers think were our top stories of the year? Rather than do an unscientific poll, we combed through our Google Analytics report and came up with the following.
While the our original story focused on a case study of human patients with venous stasis ulcers, it appears that Dermifuse/Rediheal material works shockingly well on many types of wounds. For example, the Rediheal website has several amazing animal case studies including large and small lacerations, dental void packing, and gunshot wounds. In regard to the gunshot wound case, a dog sustained at 42-square-inch wound on its back that was treated with Rediheal. According the company, the wound shrunk rapidly, and 40 days later it was nearly healed.
Corning’s “At the Speed of Light” is one of the best brief explanations about how optical fiber is made, and one that should be shown in a lot of classrooms. The step-by-step tour takes viewers from the point of conceiving double-layer, core-cladding fibers to development of high purity glass feedstock, and finally to producing miles of fiber via high throughput operations. The video succeeds because Corning let most of the story be told by the engineers and scientists who produce these fibers. Their knowledge and joy for their work comes through.
Another Corning video made the top ten list, and the company seems to be making a worthwhile investment in developing its YouTube content. This production was released on the anniversary of its first “A Day Made of Glass” video, and it fleshes out more of Corning’s vision and also incorporates some of the market trends over the last year, such as the huge success of the iPad. Some of the concepts illustrated in the video include durable, multitouch screens; colossal- and large-scale edge-to-edge displays; ubiquitous electrochromic windows; entire dashboard surfaces made of soft, flexible glass displays; lightweight auto and sunroof glass; designer-friendly photovoltaic units; antimicrobial glass services for medical applications; and even advances in glass fiber optics.
For John Mayo, who was finishing his second year as a mechanical engineering student at Texas A&M, actions speak louder than words. Want to demonstrate how strong ceramic materials can be? Well, then, how about impressing your friends by supporting a pickup truck on four coffee mugs?
A little jacking here and a few blocks of wood there, and presto: Another great video classic for the classroom!
All year, Eileen has been tracking developments related to ultrahigh temperature materials and testing (where service temperatures reach more than 1,500°C), a topic driven mostly by aerospace applications, such as hypersonic vehicles and thermal barrier coatings for jet engines, and nuclear energy applications, such as nuclear fuels and accident scenarios. In this post, Eileen reports on a paper in JACerS by Sergey Ushakov and Alexandra Navrotsky that reviews methods for measuring high temperature thermophysical properties. In the paper, the duo says, “The free energy change for a reaction can be calculated if the heat capacities, standard enthalpies and entropies of formation, and enthalpies and temperatures of phase transformations are known for all products and reactants.” But, they go on to observe that such data are often not available at temperatures over 1,500°C, and even when they are, they are subject to revision as better methodologies improve. Eileen notes that Ushakov and Navrotsky say the first essential requirement for measuring high temperature properties is accurate measurement of temperature, and the key is to choose the right method for the temperature regime. Temperatures can be measured by thermocouples or by optical pyrometry, and at these high temperatures, there are subtleties to be aware of with both.
Alta Devices is the brainchild of CalTech’s Harry Atwater and University of California at Berkeley’s Eli Yablonovitch, and its innovation is the application of GaAs on thin, flexible film substrates to make thin devices that have the highest energy density possible. Why GaAs? For starters, it can produce a current at high temperatures and in low light. The counterintuitive thing is that although GaAs is relatively expensive, Yablonovitch nevertheless says GaAs is the ideal material for making solar cells because “it absorbs photons 10,000 times more strongly than silicon for a given thickness but is not 10,000 times more expensive.” Besides setting a NREL record, the other good news for the company is that recently it demonstrated a flexible solar charger cover for iPads and similar devices that can deliver 10 watts of power. That’s a lot of juice!
University of Buffalo researchers have developed a graphene-based coating that acts as an active and passive corrosion prevention barrier and can be applied using standard, off-the-shelf industrial tools. So what? Well, for starters, corrosion costs industrialized nations approximately 3 percent of their gross domestic product or about $2-4 trillion in the US each decade. The coating is a polyetherimide matrix with a graphene filler dispersion. The polymer is a common industrial polymer, and its role in the coating is to provide adhesion with the steel as well as to provide thermal and chemical stability. The coating is effective because of it is both an active and passive coating. “It is passive in that it prevents water ions from reaching the steel,” explains UB associate professor, Sarbajit Banerjee. “We also think it works as an active coating by setting up a Shottkey barrier that depletes electrons and shuts down the electrochemistry at the interface.” Importantly, the new coating could be an effective replacement for hexavalent chromium corrosion-prevention coatings, which have been linked to cancer-causing pollution.
Another video! And, something about this creative stop-action video—made by coordinating the opening and closing of dorm room shutters on a campus in Switzerland—reminded Eileen of crystal structures and the motion of atoms, electrons, ions, holes, phonons, through a “rigid” framework. The building also seems to come alive!
This was the post where we first announced the results of R.C. Bradt and R.L. Martens research— which was soon to appear in ACerS’ Bulletin—about the apparent causes of the scattered reports of explosion like failures of transparent glass cookware used in the US. The story was recently picked up by NBC News, whose reporters investigated the claims and found reports to the Consumer Product Safety Commission to be on the upswing.
Ceramic brake rotors have been common for some time in race-oriented cars and motorcycles, and also in premium-priced commercial automobiles, and are slowly making its way into mass-market vehicles and aftermarket parts dealers. But the technology behind the current generation of ceramic braking systems isn’t all that it could be, and a team of researchers from Polytechnic Institute of New York University and Michigan-based REL Inc. say they have created a next-generation aluminum-ceramic composite brake rotor that may cut rotor weight 60 percent. The team also says the new rotor’s functionally graded design could triple the lifespan of traditional rotors. A functionally graded design is of interest because of nonuniform temperatures and pressure strains across the surface of the rotor. Instead, they say the optimal brake rotor needs to be designed with three functional regions, where each region is matched to a material with distinct strain and thermal properties.
Corrosion nibbling away on a $30 million F-15 fighter jet is a bad thing, and the paint covering one is more than camouflage—it is a sophisticated multilayer coating system that also provides corrosion protection.
A typical coating system comprises an inorganic conversion coating, a primer and a topcoat. A conversion coating is not applied directly; rather, the surface of the metal is “converted” into a coating layer by means of a chemical or electrochemical reaction. Anodizing is an example of a conversion coating. Presumably, the native oxides on metallic surfaces could be classified as a type of conversion coating, too.
Chromate conversion coatings are among the most effective corrosion-inhibiting coatings for aluminum. Most aircraft are constructed of aluminum base alloys, and, obviously, avoiding corrosion is highly desirable. Unfortunately, hexavalent chromium is carcinogenic to humans, and, in 2009, DOD committed to eliminating chromate conversion coatings from its aircraft fleet.
What to replace them with is the question that a group at the Missouri University of Science and Technology is addressing. ACerS Fellow and Society director, Bill Fahrenholtz, is working with Missouri S&T metallurgist, Matt O’Keefe, on rare earth base corrosion-inhibiting coatings. The project was named one of only six “2012 Projects of the Year” by DOD’s Strategic Environmental Research and Development Program. SERDP’s mission is to “meet DOD’s environment challenges,” through programs it sponsors in partnership with EPA and DOE.
Fahrenholtz and O’Keefe have been studying coatings incorporating rare-earth compounds of cerium and praseodymium and the mechanisms by which they inhibit corrosion. Their experiments show that rare-earth compounds are not inherently protective compounds, but, in the right circumstances, they are good alternatives to chromate coatings. Cerium-based compounds work well as corrosion protective conversion coatings. Praseodymium-based inhibitors are dispersed in the primer coating, where they migrate to the surface to inhibit corrosion.
The group is studying the coatings on substrates made of two aluminum base alloys commonly used in aerospace applications, 2024-T3 and 7075-T6. Both are susceptible to localized galvanic corrosion.
The quality of the Ce-base conversion coating is strongly dependent on processing parameters, especially surface preparation. Aluminum is an electrochemically active material, which narrows the window where good coatings are achievable. In a phone interview, Fahrenholtz says, “We walk a fine line between getting a panel that is electrochemically active enough to make the coating, but not so active that it dissolves away.” Within that narrow window, he says, processing conditions that produce the best coatings also tend to favor formation of subsurface crevices.
According to Fahrenholtz, the Ce coating covers 90 percent or more of the surface and prevents corrosion by forming a simple barrier layer. However, up to 10 percent of the surface may be exposed to crevices. Using element mapping tools, such as focused ion beam/scanning electron microscopy, the team determined that oxides form within the crevices; during the salt spray exposure, corrosion products build up within the crevice, effectively closing it as it fills with oxide and providing a self-limit to the extent of corrosion. However, they also found that the corrosion protection of the cerium conversion coatings is strongly dependent on the phase, structure, pH and processing parameters. When processed properly, the conversion coating meets the military requirement to inhibit corrosion for two weeks in the ASTM B117 salt spray test.
Praseodymium-base inhibitors are not used as coatings themselves; rather, Pr2O3 or Pr6O11 powders are dissolved in the epoxy primer coating. The dissolved praseodymium ions inhibit corrosion of the substrate by migrating through the primer to the intermetallic, electrochemically active areas of the substrate, where it forms a compound over the intermetallic regions. Fahrenholtz says the compound that forms is a praseodymium hydroxycarbonate, however, the exact phase and composition are not know. “It is a really difficult compound to isolate,” he says.
The Pr-epoxy primer approach was recognized in 2007 as a R&D 100 winner. Deft, Inc. (Irvine, Calif.) is an industrial partner on the project and incorporates the Pr inhibitors in several of its primer products.
Sounding a little like a proud father, Fahrenholtz says “Because this is now a commercial product, it’s pretty much a finished project, and our work on it is done.”
The coatings are already in-service on F-15 aircraft and Apache helicopters, and there are plans to apply them to other military aircraft systems.
Work continues, however, on the Ce conversion coatings. Fahrenholtz says there are applications for this family of coatings in commercial aviation, military aviation and automotives. He says automobile weight reduction, for example, drives the development of materials like aluminum and magnesium, which are more reactive and need to be protected from the environment.
Mars Curiosity discovery revealed: complex chemistry in soil with possibility to form organic materials
This isn’t really ceramics or glass related, but a follow up to a story I wrote last week about the Curiosity’s “SAM” soil analysis lab (which, as NASA aptly describes, is a CSI-like unit). This morning NASA revealed what “remarkable” thing it found already in its two-year exploratory effort.
Highlights from SAM: The rover apparently landed in what NASA still believes is an ancient river bed and the unit found water and sulfur, chlorine-containing substances, common volcanic minerals, and about half of the samples’ contents were noncrystalline materials such as glass. The presence of the chlorine was particularly intriguing, and SAM was able to detect clorinated organic compounds (CH3Cl, CH2Cl2, CHCl3) that NASA scientists believe are the results of the breakdown of perchlorate salt or perchlorate-like compounds when heated in SAM ovens. SAM also found water, CO2, O2, SO2 in the vapors of the heated material.
Somewhat surprisingly, the rover determined that the deuterium-to-hydrogen ratio is five times what it is on earth but varies with the Martian season. They also say it appears that, in general, there are higher amounts of heavier isotopes in sulfur and nitrogen, and probably other elements (they say the lighter ones likely were lost via the atmosphere to space).
Going back to the issue of the perchlorate and organic compounds, NASA acknowledges that perchlorate had previously been found on Mars’ arctic region. However, if I understand NASA correctly, the new findings suggest an abundance of perchlorate and the ability to form chlorinated organics. NASA says the results need to be greeted with caution because it still needs to confirm that carbon in the compounds is Martian in origin and not from Earth.
NASA’s John Grotzinger, whose interview with NPR touched off the hype about this discovery, was asked in a live press conference what he believed was the most important discovery. He said that, for him, the importance lies in several things: the apparent finding organic or pre-organic compounds in “globally representative material,” the ability of all of the analytical instruments to feed into results and then seeing the experiments repeatedly provide the same results.
Another reporter asked Grotzinger about his reaction to the the hype around the discovery. Grotzinger admits, “I learned that you have to be careful about what you say and how you say it… perhaps the enthusiasm we are having for this project is just misunderstood.”
Regarding next steps, the NASA reps say that if they determine that carbon is of Martian origin, they next will be looking at isotope ratios of the carbon in the compounds to determine whether it is of a biotic origin.
Here is a link to NASA’s news release on the announcements today.