Greg Rohrer talks about the goals, process and findings of a recent workshop organized to identify the scientific grand challenges and emerging research areas relating to ceramic materials. Credit: ACerS.

What are the big questions that ceramic materials can answer?

In March a group of about 35 ceramic scientists gathered for a workshop funded by the National Science Foundation with the task of identifying the most important scientific challenges facing the ceramics community and the areas of emerging research that the ceramic materials research community should make its priority.

The group also talked about ceramic materials research in an international context and the role of the NSF in supporting ceramic materials research. The consensus seemed to be that scientific research today is collaborative with an international reach, and that the NSF’s Materials World Network is effective at supporting those collaborations.

The workshop represented the full spectrum of ceramics researchers with participants from academia, government and industry. By the end of the workshop, eight categories of scientific challenges emerged. The workshop’s activities and findings will be reported in the Journal of the American Ceramic Society in a paper that will detail the process and include supporting graphs, images, references, etc. Also, the workshop’s organizer, Greg Rohrer, will give a talk on the grand challenges at the ICC4 event in July.

Rohrer, professor and head of the materials science department at Carnegie Mellon University, also is coordinating the follow-up and dissemination of the workshop’s collective findings. At the end of the workshop, he took a few minutes to describe (see video) the workshop, its goals, the process used to tease out the grand challenges and how the group’s conclusions will be disseminated.

Rohrer provided a draft executive summary of the eight challenges that were identified, and they are summarized below. They will be refined further for the paper and presentation, but will probably not stray too far from these.

Understanding rare events
Lifetimes of ceramics in many applications are particularly sensitive to rare (sometimes described as statistical) events. Although statistical techniques, such as those developed by Weibull, satisfy the needs of design engineers, they offer little understanding of the underlying causes of life-limiting phenomena. The challenge is to understand the causes and mechanisms by which rare events lead to failure. Recent advances in methods for the complete three-dimensional characterization of structure and composition, coupled with the expanding capabilities of multiscale simulation techniques that reveal the relationship between microstructure and functionality, will bring the goal within reach during the next 5-10 years. This fundamental understanding has the potential to lead to materials that demonstrate feedback through self-sensing and self-healing functions, leading to materials with extended lifetimes and enhanced sustainability.

Oxide electronics
The challenge is to design and synthesize oxide surfaces, interfaces and nanoscale structures that catalyze a wide spectrum of scientifically inspiring electronic properties, including high mobility, superconductivity, and magnetism, that can be tuned by external electrical, optical, magnetic, mechanical and chemical stimuli. Because of their non-linear properties, oxides have the potential to reveal phenomena not possible in conventional group IV and III-V semiconductor electronics. Crystal growth and design, the control of defects and integration with other materials are all issues associated with this challenge.

Metastable defects in the vicinity of interfaces
The fundamental thermodynamic theory for point defects explicitly ignores the interface structure and proximity to interfaces that act as sources and sinks. However, in nanostructured materials and devices, interfaces are integral parts of the structure and may dominate properties. The challenge is to extend defect chemistry models to account for the metastability of defect distributions in nano-heterogeneous ceramic systems where surfaces and interfaces are closely spaced. Models for defect distributions in these conditions must also account for the composition of the gaseous environment, high pressure and temperature as well as high strain (often present in heterostructures) and high electric fields.

Control of ceramics far from equilibrium
It is now possible to prepare materials that have extremely high surface areas because of their internal porosity, very small particle size, or because they are comprised of quasi one-dimensional (fibers) or two-dimensional (exfoliated layers) components. However, it remains a challenge to predict how the thermodynamic, physical, structural and functional properties of materials prepared far from equilibrium differ from those of the bulk equilibrium phases and how these properties change with composition and grain size. It is also necessary to understanding when such materials have acceptable lifetimes in applications and when they evolve to other states, which often compromise function. There must be greater synergy between theory-computation-modeling and experimental measurements, with the former providing mechanistic insights at the molecular scale and identifying areas where new measurements are needed, and the latter benchmarking the accuracy of the former.

Ceramics: Going beyond boundaries
Interfaces between two phases or between two misoriented grains of the same phase traditionally were thought to have relatively constant properties that vary continuously with temperature. However, a new paradigm for understanding interfaces has emerged that allows the possibility for abrupt transitions in their structures and properties. This new understanding opens up the possibility of producing microstructures with well-controlled grain size distributions and texture. This degree of control makes it possible to imagine nanostructured, heterogeneous composites with new combinations of macroscopic properties, making it possible to move into the “white spaces” of Ashby property diagrams.

Predicting heterogeneous microstructures with unprecedented functionalities
Among all materials classes, ceramics offer the widest breadth of chemistry, bonding and structure, and their combinations with each other and other materials enable the realization of unprecedented functionalities. These functionalities depend on the properties of the constituents and their microstructure at different length scales. Emerging processing, simulation and materials characterization techniques make it possible to understand scientifically complex structure-function relationships. The challenge is to use these new capabilities to develop materials with ultrahigh temperature stability, high ionic conductivity at room temperature and batteries that can charge in minutes and last hours.

Accelerated the development of new ceramic materials
While there exists a wide range of synthetic paths for new ceramics, we are not yet able to make new materials in a sensible and systematic fashion and to explore the physical properties of such materials with an eye to unique behavior and novel applications. The goal is to create totally new types of ceramics rather than to modify existing ones by small changes in composition or processing. This area is especially fruitful for materials containing several anions, e.g., B, N, C, chalcogenides, halides, etc. Addressing this challenge will require guidance from computation on target compositions and synthesis strategies, as well as a merging of the practices of the synthetic chemist and ceramist.

Harnessing order within disorder
The development structure-property relationships for disordered materials are limited by our lack of knowledge of short- to intermediate-range order (non-random structure beyond the first two or three coordination shells). This is a long-standing problem in glasses and glass-forming liquids. New experimental techniques for the observation of intermediate-range order, interpreted using the results of increasingly powerful simulations, will lead to new models for the relationship between intermediate-range order and glass properties in the next five to ten years. This understanding promises to lead to improved functionality, including strength and related benefits with respect to energy consumption and sustainability.

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My colleague and pal, Megan Bricker, who is ACerS director of marketing and membership, looked up a few things to do while in Chicago. We’ll know where to look if we cannot find her!:

It’s time to make travel arrangements to Chicago for the 4^th International Congress on Ceramics with the 3rd Ceramic Leadership Summit Track. Not only is this conference providing first-class speakers on ceramic and glass issues that are shaping the future of ceramics, but it also is being held in one of the United States’ most popular cities—Chicago.

With its world-renowned museums, parks, shopping, architecture, music and food, Chicago is one destination city you won’t want to miss. Set on the beautiful waters of Lake Michigan, this city offers visitors of all ages plenty to see and do.

And, no one knows Chicago better than those who live there. ACerS member Jorge Ayala of Superior Graphite, Co. lives and works in Chicago. He says it’s simply an amazing city:

“One of my favorite things to do is to take a walk in Millennium Park. The view of the lake is spectacular. And, if you are in Millennium Park, you will be close to the Art Institute of Chicago and the Field Museum. Both are fabulous for visitors of all ages,” said Ayala.

In fact, the ICC4 conference’s closing banquet will be held in the stunning, new modern wing of the Art Institute of Chicago for all attendees and companion registrants.

If you are in the mood for shopping, look no further than Chicago’s famous Michigan Avenue, otherwise known as the “Magnificent Mile.” Chicago is home to more than 400 fashion designers and Michigan Avenue is lined with name brand shops and small whimsical boutiques.

While you are out shopping, take a good look around. You will see why visitors from all over the world come to see the birthplace of modern buildings and are in awe of Chicago’s cityscapes and architectural marvels.

If traveling with children, (and for “kids” of all ages”) I would personally recommend a stop at the Navy Pier to go to Chicago’s Children’s Museum where kids can explore three floors of fun and interactive learning. While there, I also wouldn’t miss the Smith Museum of Stained Glass, which is FREE to all visitors. A perfect night for me would end with delicious Chicago style deep-dish pizza and a drink at one of the amazing blues or jazz clubs.

If discovering the city on your own isn’t for you, then sign-up for one of the conference’s optional tours, one of which is to nearby Argonne National Laboratory.

There is so much to see and do in Chicago, you just might want to pack some extra clothes and stay a few more days. You’ll be glad you did.

As a native Chicagoan myself (even though it’s been a few … decades), here are a few of my favorite destinations not mentioned above:

• The Mueum of Science and Industry, with featured special exhibition, “MythBusters: The Explosive Exhibition.
• Wrigley Field, home of the Chicago Cubs (faith endures—maybe this is their year!).
• Berghoff’s, a downtown Chicago lunchtime institution and a uniquely Chicago experience.
• Willis Tower, test your faith in the strength glass in the “birdcage” observation decks.

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The efficiency of LED devices is limited by carbon point defects in the aluminum nitride transparency layer, which absorb useful wavelengths of light (around 4.7 eV). North Carolina State University researchers used computational methods and detailed experiments to make the discovery. Credit: Doug Irving; NC State.

The Materials Genome Initiative is shining the spotlight on modeling, simulation and computational methods for materials science, mostly for materials development.

Computational methods can be used to solve old problems, too, as a recent paper published by a group out of North Carolina State University demonstrates.

The 30-year old problem relates to absorption of ultraviolet light by single crystal aluminum nitride, a semiconductor that is used as a substrate for AlGaN-based UV emitting LEDs and laser diodes. Because these devices emit UV, they could be used to kill pathogens, for example, in drinking water or on surgical instruments. In a university press release, lead author Ramón Callazo says, “UV treatment utilizing LEDs would be more cost-effective, energy efficient and longer lasting.” Callazo is an assistant professor of MSE at NC State.

However, taking advantage of the UV-emitting property has been difficult because the substrates themselves absorb a fair amount of the UV.

Using density functional theory calculations, a research team at NC State determined that trace amounts of carbon were the culprit and that, according to the abstract, “substitutional carbon on the nitrogen site introduces absorption at this energy.” The team followed up by characterizing a series of single crystal wafers and showed that the absorption band increased linearly with increased carbon.

In a press release, coauthor Zlatko Sitar, professor of MSE at NC State, says,” Once we identified the problem, it was relatively easy and inexpensive to address.” HexaTech Inc., a university spin-off company that specializes in growing single crystal aluminum nitride, is already working on incorporating the research into its technology.

Of the 30-year old problem, Doug Irving, also a coauthor and department assistant professor, says in the press release, “we were able to solve it by integrating advanced computation, material synthesis and characterization. I think we’ll see more work in this vein as the Materials Genome Initiative moves forward, and that this approach will accelerate the development of new materials and related technologies.”

The paper is, “On the origin of the 265 nm absorption band in AlN bulk crystals,” is published online in Applied Physics Letters, http://dx.doi.org/10.1063/1.4717623.

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Credit: Notebooks: YouTube.

You don’t have to be a hard head to appreciate this: Kyocera demonstrated this week a new audio technology for cellphones (and likely a wide range of other applications) using a system that is designed to clearly transmit sound waves through tissue and bone. The company has replaced the traditional cell phone speaker with a system based on proprietary ceramic transducer technology. The phone can still be heard a few inches from the user’s head, but the transducer system really comes into play when the phone is touched to the ear or on the skull near the ear.

The utility of this? I can think of lots of times when I have been in a noisy conference reception or a sporting event and get a call on my cellphone: I typically can’t hear what the caller is saying and have to dash off to an exit or quiet corner to complete the call. As described in the above video, Kyocera claims its technology can provide crystal-clear sound even in noisy environments—sort of like noise-cancelling earphones, but no noise has to be cancelled because the transducer’s actions produce an alternate pathway for vibrations to the ear canal and inner ear than the ambient noise.

As Kyocera notes, there also are times when employees (they mention aircraft ground crews) wear bulky ear protection devices that must be worn, and there is no possibility of going to a quieter place. The company says a phone with its technology can be held up to the ear cans and be well heard.

The company says the phones with the technology will be brought quickly to market, first in Japan and later on in the United States and other markets.

Kyocera’s system was introduced at the International CTIA Wireless 2012 Conference that just wrapped up in New Orleans.

ADDING: After doing some more digging around, I found that the Kyocera technology was apparently also demo’ed early this year, although in KDDI phones. (Background: There is a connection between KDDI and Kyocera: Both were founded by the legendary ceramics leader, Kazuo Inamori.) The narrator of the video obviously didn’t really understand the transducer end of things, but he does demonstrate how the sound works either by means of direct ear contact or vibrations through a set of protective earphones or even metal microphone!

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Here is what we are hearing:

Unifrax celebrates 70 years of success with Fiberfrax product line

Unifrax, a leading global producer of high temperature fiber products is celebrating a milestone year in 2012 as it observes the 70th anniversary of its well-known Fiberfrax product line. In 1942, J. Charles McMullen was a research scientist for The Carborundum Co. Fibers Division, later known as Unifrax, when he invented a revolutionary ceramic fiber that was trademarked under the Fiberfrax name. Today, the spirit of innovation continues at Unifrax where over 50 Fiberfrax product forms, as well as Insulfrax and Isofrax soluble fiber products are backed by experienced Unifrax application engineers, customer service team and extensive distributor. “The success of the Fiberfrax product line during the past 70 years is due to the shared expertise, dedication and support of our customers, distributors and employees,” says Unifrax president, David E. Brooks. “We are committed to continuingthe tradition of high quality, innovative products and service that are an integral part of the Fiberfrax brand.”

CoorsTek acquires ANCeram GmbH & Co. KG Technical Ceramics

CoorsTek (Golden, Colo.) has purchased ANCeram GmbH & Co. KG of Bindlach, Germany. Known primarily for its extended range of specialty aluminum nitrides, ANCeram manufactures ceramic substrates, insulators, and structural components for the aerospace, laser, railway, marine, and automotive industries. Established in 1988, the early focus for ANCeram was on creating a superior alternative for environmentally challenging beryllium oxide. Working with several European universities and independent research centers, ANCeram developed their own environmentally friendly aluminum nitride ceramic. In addition to their broad AlN experience, the company offers silicon nitrides, aluminas, copper-to-ceramic brazing capabilities, ceramic-to-metal bonding, and ceramic metallization. Products include components for insulators, coolers, diodes, heat exchangers, power electronics, high-temperature crucibles and boats, and other multimaterial components.

Carbo Ceramics to construct manufacturing plant and create 70 new jobs

Carbo Ceramics Inc. will begin construction on a state-of-the-art ceramic manufacturing plant in Millen, Ga., announced Gary Kolstad, president and CEO. Having received its air quality permit from the State of Georgia, Carbo should commence construction on the first production line by the end of 2012 and operations could begin near the end of 2013. Initial staffing for the plant should create 70 new jobs in Jenkins County. The project will bring up to 300 construction jobs to the area during assembly of the plant. The manufacturing plant will be situated on 450 acres and conveniently located for product distribution by truck or rail. In addition to the distribution flexibility, the site has the ability to expand to four production lines. Ceramic proppant is used in hydraulic fracturing to make oil and gas wells produce better and recover more oil and gas.

Morgan Thermal Ceramics offers refractory monolithic material for high temperature applications

Morgan Thermal Ceramics announces the availability of its high-strength, low-cement range of refractory monolithic lining materials ideal for demanding, high temperature applications in the metals, incineration, power generation and minerals processing markets. The full range of products includes Tri-Mor Morflo low cement castable and Tri-Mor Higun low cement gunning materials. They offer excellent resistance to chemical attack and abrasion, combining the traditional high performance qualities of high fired brick with the ease of installation of a refractory castable. These advanced materials are ideal for use in forge furnaces, rotary kilns, rotary hearths, pusher furnaces, skid kid pipe protections and troughs for molten copper. The availability of the full range of products offers significant benefits, as walls and floors can be lined with the Morflo castable material, while roofs can be gunned with the complementary Higun material.

Sasol expands ultrahigh purity aluminas capacity

Sasol Ltd.’s Olefins & Surfactants Division (headquarters in Hamburg, Germany) announced it will expand in a first step its capacity to produce ultrahigh purity aluminas by at least 3,000 metric tons per year. Construction will begin immediately at Brunsbuettel, the company’s Germany manufacturing site on a process to supply Sasol North America’s Ceralox alumina production facility in Tucson, Arizona with ultrahigh purity alumina precursor. Sasol Olefins & Surfactants, a provider of ultrahigh purity alumina materials for sapphire and other applications for more than 20 years, will then convert the Brunsbuettel alumina precursor into tailored products for customer specific applications. Of particular focus to Sasol are the increasing raw material requirements of single crystal sapphire producers due to rapidly growing LED applications.

Heraeus continues on record course in 2011

The Hanau-based Heraeus precious metals and technology Group in 2011 once again surpassed the previous year’s record results, tallying the most successful year in the company’s history. This was announced by the Heraeus Holding GmbH Board of Management at a press conference on annual results held in Frankfurt on May 10. With product revenues of EUR4.8 billion, Heraeus surpassed the previous year’s level by 19 percent. Operating results (EBIT) also increased by 23 percent to reach a total of €489 million. Precious metals trading revenue reached €21.3 billion, topping the €20 billion threshold for the first time. This represents an increase of 19 percent over the previous year’s level. The outlook for 2012 is good, too.

Babcock and Wilcox executives see bright prospects in coal power plants despite natural gas competition

Via the Akron Beacon Journal —Prolonged low natural gas prices in the United States likely will hurt some of Babcock & Wilcox’s coal power plant-related business, the company’s top executives said Thursday. But any impact that reduces coal power plant usage in the U.S. can be minimized in part because B&W expects to gain business through its technology and services that make coal-fired plants environmentally cleaner, they said in an earnings conference call with industry analysts. In addition, B&W sees strong demand for coal-fired plants elsewhere in the world, particularly Asia, where natural gas prices are not as low as in the United States, they said.

New Harper webinar series: Designing for energy efficiency in thermal processing

Harper International is proud to present new webinars from our seasoned experts focused on maximizing the production economics of your thermal processing system. In our multi-part series, you will get access to the know-how of Harper’s industry-leading experts, with decades of experience in thermal processing for a variety of advanced materials and expertise in helping customers grow their thermal processing lines successfully. The first webinar will be June 5, 2012, at 11 a.m. (Eastern Time). The webinar will be led by Robert Blackmon, vice president of integrated systems, and Doug Armstrong, process technology engineer. This webinar will explore how to optimize high temperature processes; considering efficiency early during development of advanced material processes; reuse of furnace outputs to drive down utilities costs; batch vs. continuous processing; pragmatic retrofits to apply to existing systems; and carbon fiber as a case study example.

Harrop increases toll firing capacity at Columbus facility

Harrop Industries has recently commissioned two new electrically-heated elevator kilns in its toll firing facility in Columbus, Oh, to fulfill the ongoing demand from our clients. Harrop now operates 17 electric and gas-fired periodic kilns and ovens with temperature capabilities up to 1,700°C and atmosphere control. With the wide variety of equipment available, Harrop can tailor a solution to meet our clients’ needs in both product development and supplemental production. Founded in 1919, Harrop has been and continues to be a leader in custom designed industrial kilns for the ceramics industry. Our breadth of knowledge in thermal processing equipment has also allowed us to supply custom heat treating systems in other industries as well. Our focus is to build relationships with our clients and provide a system that is custom designed for their process.

Union Process introduces DMQX bead mill

Union Process, Inc., known globally as a leading manufacturer of size reduction and dispersing equipment for a broad range of industrial applications, has launched the DMQX horizontal bead milling system. The DMQX mill features an enhanced disc/rod design that significantly improves grinding efficiency. The new design dramatically increases milling effectiveness resulting in shorter milling time and lower shaft speeds. The result is less wear on seal faces and other wear parts, which in turn results in significant cost savings. The unique design of the mill allows for a fast and efficient solution for producing materials in the single micron and even nanometer range, all with the cost-effective advantages of circulation grinding. Union Process is the inventor and developer of attritor technology, and manufactures wet and dry grinding mills as well as horizontal bead mills.

Remtec expands DBC substrate capabilities, provides fast prototyping and delivery of low/medium volume DBC substrates

Remtec, a leading manufacturer of substrates and packages with Plated Copper On Thick Film, has significantly expanded its activity in the design and fabrication of DBC ceramic products for military and commercial applications in small to medium production volumes with fast prototyping and economic pricing. This capability is supported by close cooperation with Rogers Corp. to provide Remtec with its standard Curamik brand mastercards. Remtec facilitates fast turnaround by keeping an extensive stock of the most commonly used 5.5″ x 7.5″ alumina and aluminum nitride DBC configurations ready for production. Remtec utilizes the well-known quality of Curamik DBC substrates coupled with high quality Remtec plating typical of its PCTF products. Remtec offers its customers versatile surface finish options such as selective gold, gold tin plating, and ENEPIG. These processes along with various solder mask options allow for high reliability, low cost solutions suitable for any assembly technique.

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