Susan Trolier-McKinstry to deliver Friday’s EMA plenary after AFOSR speaker cancels.

Last week I wrote about a memo sent by the deputy secretary of DOD to the entire agency encouraging proactive spending cuts, including cutbacks on travel, conferences, and training. It did not take long for DOD brass to embrace the recommendations, and we just got word that this week’s Electronic Materials and Applications meeting is affected. Unfortunately, the Friday morning plenary speaker, Kitt Reinhart, program manager at the Air Force Office of Scientific Research, did not get approval to attend the meeting and give the plenary talk.

The good news is that Susan Trolier-McKinstry from Pennsylvania State University has agreed to step up and deliver the Friday plenary talk. Her plenary talk is ”Designing Piezoelectric Films for Microelectromechanical Systems (MEMS)” and the abstract follows. She also is coauthor of three talks and chairing a session in the “Functional and Multifunctional Electroceramics” symposium. Busy lady!

ACerS and the Basic Science Division and the Electronics Division appreciate the generosity of both Reinhart and Trolier-McKinstry to share their time and expertise!

“Designing Piezoelectric Films for Microelectromechanical Systems (MEMS)”

Susan Trolier-McKinstry, Materials Science and Engineering Department and Materials Research Institute, Pennsylvania State University

Abstract
Piezoelectric thin films are of increasing interest in low voltage microelectromechanical systems (MEMS) for sensing, actuation, and energy harvesting. They also serve as model systems to study fundamental behavior in piezoelectrics. Piezoelectric MEMS devices range over a wide range of length scales. On the extreme upper end are large area devices for applications such as adaptive optics. In this case, the piezoelectric film can be used to produce local deformation of a mirror surface, in order to correct figure errors associated with fabrication of the component or to correct for atmospheric distortion.  For example, should a mission such as Gen-X be flown, it would require up to 10,000 square meters of actuatable optics in order to correct the figures of the nested hyperboloid reflecting segments. In this case, the “micro” in “microelectromechanical systems” is clearly a misnomer, although the fabrication techniques would involve conventional micromachining for patterning of the electrodes. Many Piezoelectric MEMS devices are fabricated at intermediate length scales (tens of microns to 1 centimeter). Here, examples will be given of piezoelectric energy harvesting devices. We have recently demonstrated improvements in the energy harvesting figure of merit for the piezoelectric layer by factors of 4–10. Finally, piezoelectric MEMS are also attracting attention at a substantially smaller size scale (tens of nanometers) as a potential replacement for CMOS electronics. Examples of the materials choice as well as specific devices at all three of these length scales will also be discussed.

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There a lot of great stuff going on:

Atoms at negative absolute temperature: The hottest systems in the world

On the absolute temperature scale that is used by physicists, the Kelvin scale, one cannot go below zero—at least not in the sense of getting colder than zero Kelvin. Physicists of the Ludwig-Maximilians University Munich and the Max Planck Institute of Quantum Optics, Garching, Germany, have now created an atomic gas in the lab that has nonetheless negative Kelvin values. These negative absolute temperatures lead to several striking consequences: Although the atoms in the gas attract each other and give rise to a negative pressure, the gas does not collapse, a behavior that is also postulated for dark energy in cosmology. Also supposedly impossible heat engines can be realized with the help of negative absolute temperatures, such as an engine with a thermodynamic efficiency above 100 percent. In order to bring water to the boil, energy needs to be added to the water. During heating up, the water molecules increase their kinetic energy over time and move faster on average. Yet, the individual molecules possess different kinetic energies, from very slow to very fast. In thermal equilibrium, low-energy states are more likely than high-energy states, i.e., only a few particles move really fast. In physics, this distribution is called Boltzmann distribution. Physicists led by Ulrich Schneider and Immanuel Bloch have now created a gas in which this distribution is inverted: Many particles possess large energies and only a few have small energies. This inversion of the energy distribution means that the particles have assumed a negative absolute temperature. “The inverted Boltzmann distribution is the hallmark of negative absolute temperature; and this is what we have achieved,” says Schneider. “Yet the gas is not colder than zero Kelvin, but hotter. It is even hotter than at any positive temperature. The temperature scale simply does not end at infinity, but jumps to negative values instead.”

‘Greenest street in America’ to provide data on smog-eating concrete

(GizMag) A streetscape that includes natural landscaping, bicycle lanes, wind powered lighting, storm water diversion for irrigation, drought-resistant native plants and innovative concrete has earned Cermak Road in Chicago the title of “Greenest Street in America” according to the Chicago Department of Transport (CDOT). The location runs through an industrial zone which links the state and US highways. The project will record quantifiable results through a set of equally aggressive sustainability goals charting eight performance areas such as storm water management, material reuse, energy reduction, and place making. The most anticipated data will be collected from the first commercial use of photocatalytic cement for the inside highway lanes. This “smog eating” cement contains nano particles of titanium dioxide and is designed to clean the surface of the road and remove nitrogen oxide from the surrounding air through a catalytic reaction driven by UV light. In addition CDOT used 30 percent recycled content in the sidewalk concrete.

Penn researchers show new level of control over liquid crystals

Researchers from the University of Pennsylvania have shown a new way to direct the assembly of liquid crystals, generating small features that spontaneously arrange in arrays based on much larger templates. “Liquid crystals naturally produce a pattern of close-packed defects on their surfaces,” says Shu Yang, leader of the study, “but it turns out that this pattern is often not that interesting for device applications. We want to arbitrarily manipulate that pattern on demand.” Electrical fields are often used to change the crystals’ orientation, as in the case with liquid crystal displays, but the Penn research team was interested in manipulating defects by using a physical template. Employing a class of liquid crystals that forms stacks of layers spaced in nanometers—known as “smectic” liquid crystals—the researchers set out to show that, by altering the geometry of the molecules on the bottommost layer, they could produce changes in the patterns of defects on the topmost. “The molecules can feel the geometry of the template, which creates a sort of elastic cue,” says another research, Kathleen Stebe. “That cue is transmitted layer by layer, and the whole system responds.” The researchers’ template was a series of microscopic posts arrayed like a bed of nails. By altering the size, shape, symmetry and spacing of these posts, as well as the thickness of the liquid crystal film, the researchers discovered they could make subtle changes in the patterns of the defects.

DARPA injected miracle foam could save lives on the battlefield

(Government Executive) DARPA has developed an injectable foam that shows promise in reducing death from internal bleeding, especially in situations involving noncompressible wounds. Two separate liquid compounds are injected in the body. When the two liquids mix, they react to form a foam coagulant that expands within the abdominal cavity-compressing the wound without sticking to vital organs. In tests, the compression was shown to reduce blood loss by six-fold and increase the three hour survival rate to 72 percent, up from just eight percent. DARPA Wound Stasis program manager Brian Holloway says, “If testing bears out, the foam technology could affect up to 50 percent of potentially survivable battlefield wounds.”

Inflatable private space stations: Bigelow’s big dream

NASA’s decision to buy an inflatable new room for the International Space Station may push the module’s builder—commercial spaceflight company Bigelow Aerospace—one step closer to establishing its own private stations in orbit. Last week, NASA announced that it will pay $17.8 million for the Nevada-based company’s Bigelow Expandable Activity Module (BEAM), which will be affixed to the huge orbiting lab as a technology demonstration.

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Here is what we are hearing:

Netzsch to supply SpaceX’s thermal analysis lab

Netzsch Instruments North America LLC is proud to announce that it is currently the sole supplier to Space Exploration Technologies Corp. (SpaceX) of high temperature thermal analysis instruments used to characterize material properties for space applications. SpaceX was founded in 2002 by Elon Musk to revolutionize space transportation, with the ultimate goal of enabling people to live on other planets. Netzsch’s instruments will be used to fine tune properties of existing materials and to develop new materials for use in the demanding, harsh environments of space. The ability of Netzsch to custom engineer and modify the instruments to meet SpaceX’s requirements was a key factor in their choice of vendors. Mission critical material will be developed, tested and modeled using data from Netzsch’s Thermokinetics software. Netzsch instruments also will be used to measure basic material properties along with other thermophysical properties. Some of these properties will include 1st, 2nd and 3rd order transitions, coefficient of thermal expansion and contraction, modulus, energy adsorption dampening, heat capacity, thermal diffusivity, thermal conductivity along with software and heat transfer data to model and build heat management systems.

Visiongain: Global ceramic coatings market to be worth $5.98B in 2013

Visiongain, a business market research group based in London, has issued an analysis that indicates that the global ceramic coatings market will reach a value of $5.98 billion in 2013, as emerging market demand for various consumer items indirectly increases demand for ceramic coatings, and as the need for cost-effective solutions for ceramic coatings to improve productivity and efficiency of machining equipment grows in importance. The ceramic coatings market is therefore forecast by Visiongain to record solid growth over the next decade, as ceramic coatings become more popular. The company also noted that ceramic coatings are in demand in the developed world, where they are increasingly used to improve efficiency and productivity, and strengthen parts, delivering cost-savings.

Sage files patent infringement lawsuit in U.S. District Court against View Inc.

Sage Electrochromics Inc., a world leader in the development and manufacture of dynamic glass, located in Faribault, Minn., has announced it has filed a lawsuit in U.S. District Court, Northern District of California, against View, Inc. (formerly Soladigm, Inc.) of Milpitas, Calif. “We filed this lawsuit to enforce our patented intellectual property that protects our substantial investment in developing our pioneering, game-changing dynamic glass technology” The nature of the lawsuit is a complaint for patent infringement involving U.S. Patent #5,724,177 entitled “Electrochromic Devices and Methods” and U.S. Patent #7,372,610 entitled “Electrochromic Devices and Methods.” Sage is seeking damages and injunctive relief to prevent View Inc. from continuing to infringe on Sage’s intellectual property. “We have worked for more than twenty years to bring our patented electrochromic glass to market, ” says John Van Dine, CEO, founder of Sage, and coinventor of the ‘177 patent. “Our hundreds of installed projects and delighted customers validate our research and intellectual property. We believe we will prevail in this important case. We look forward to continuing our long heritage of bringing innovations in dynamic glass to our global clients.”

MTC announces extensive range of mastics for maintenance and hot spot repair

Morgan Thermal Ceramics announces the availability of an extensive range of pumpable mastics, ideal for maintenance and repair of hot spots in the power generation industry. Complementing a full line of fiber and refractory insulation products, the Mastics range includes pumpables and moldables. Hot spot repair pumpables are designed for injection filling of refractory joints and cracks, even while the boilers are in operation. Rather than shutting down the furnace and idling it for days or weeks until the temperature cools, resulting in potentially costly downtime, pumpable wet fiber technology can be used to make repairs within hours. Designed for pumping into voids caused by deteriorated insulation, grouting cracks and gaps in refractory linings, these pumpable products are ideal for providing quick and easy re-insulation behind boiler tubes in sidewalls, seals and floors, as well as repairs of ovens, furnaces and process equipment.

Orbite Aluminae Inc. named as national winner of Canada’s 2012 new technology awards

Canadian Manufacturers & Exporters, in collaboration with the National Research Council of Canada Industrial Research Assistance Program, recognize Orbite Aluminae Inc., based in Montréal, Québec, as national winner of the 2012 Regional Awards for New Technology. Orbite is a Canadian cleantech company whose innovative technologies are setting the new standard for alumina production. Orbite technologies enable environmentally neutral extraction of smelter-grade alumina, high-purity alumina and high-value elements, including rare earths and rare metals, from a variety of sources such as aluminous clay and bauxite, without generating toxic red mud residue. Orbite’s operations have a negligible environmental impact compared to the conventional process of extracting alumina from bauxite. The Orbite process of producing metallurgical-grade alumina involves crushing and then acid leaching the aluminous claystone found at the company’s Grande-Vallée property. Orbite’s unique technology consumes less energy and generates less pollution then and no caustic by-products. The award recognizes innovative excellence in the development, adoption, and application of new technology in process or products.

Cabot Aerogel introduces industrial insulation blanket for high temp applications

Cabot Corporation announces that it has developed the Aeroclad blanket, a flexible high-temperature insulation material formed by integrating Cabot’s silica aerogel within a non-woven, inorganic fiber batting. The Aeroclad blanket delivers a dust free, flexible wrap that takes advantage of the superior thermal insulation performance and hydrophobic nature of aerogel. Cabot has created this new aerogel blanket product with exceptional corrosion-under-insulation (CUI) characteristics, and without dust, to significantly outperform the currently available competing products. The blanket can be field-modified and easily installed for use in a wide range of industrial applications such as pipelines, refineries, steam lines, tanks, and other equipment. Aeroclad insulation delivers more than twice the thermal insulation protection compared to conventional high temperature insulation materials such as mineral wool, calcium silicate, and fiberglass. The blanket also offers significantly lower water retention and faster drying, minimizing the potential for CUI.

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Image of Martian surface, likely an ancient riverbed, where Curiosity’s SAM instruments scooped samples that NASA scientists believe they have found signs of organic materials. Credit: NASA.

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, SO_{2 in the vapors of the heated material.}

Gases found in SAM analysis. Credit: NASA.

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.

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Schematic of SAM (Sample Analysis at Mars) soil and atmospheric analysis unit, part of Curiosity’s Mars Science Laboratory. Credit: NASA.

If you have spent any non-shopping time on the Internet over the last week, chances are you probably read or heard something about a pesky interview National Public Radio correspondent Joe Palca did with the principal investigator of the NASA Mars Curiosity rover mission, John Grotzinger, in which the latter mentioned that something remarkable popped up in a recent Martian soil sample—remarkable enough for Grotzinger to tell Palca, “This data is gonna be one for the history books. It’s looking really good.”

Grotzinger refused to elaborate even a smidgeon, begging off any details for NPR or any other news outlet until the tests could be confirmed. This, unsurprisingly, set off all sorts of speculation about what is up NASA’s sleeve that has ranged from the reasoned to the wild to the humorous (insert your own DB Cooper, Jimmy Hoffa or birth certificate joke here).

The mystery behind Grotzinger’s comments is expected to be revealed in the near future, and he and Palca probably hope it’s sooner rather than later because both have received substantial criticism for whether they exceeded the professional bounds of science and journalism by letting this quasi-story see the light of day. In fact, details may be forthcoming next week when an announcement is expected at a press conference at American Geophysical Union Annual meeting, but NASA yesterday formally attempted to lower expectations.

Regardless of what NASA eventually reveals, it turns out there is a piece of ceramic, formed by an additive manufacturing process—stereolithography—that will have played a significant role in the soil analysis. This piece is a special alumina ceramic heater housing produced by Technology Assessment and Transfer Inc., a small defense and government contractor based in Annapolis, Md.

Alumina heater housing formed via stereolithography. Credit: TA&T Inc.

The ceramic heater housing is an indispensable component of the rover’s SAM (Sample Analysis at Mars) instrument suite. SAM’s meat-and-potatoes work occurs when volatile materials from the Mar soil samples are fed into the suite’s six-column gas chromatograph, a quadrupole mass spectrometer and a tunable laser spectrometer.

However, before the GC, QMS and TLS can do their important work, the soil must be carefully prepared to release the volatile components—and that is where the ceramic heater body comes in. It is a dimensionally small-but-central part (only 0.75″ long with an external diameter of 0.5″ and an internal diameter of 0.38″) of several ovens in SAM’s Sample Manipulation System where solid phase materials are sampled by transporting finely sieved materials to one of 74 SMS quartz sample cups. The cups are inserted into the special oven and heated to release volatiles. The ovens also help clean the cups for reuse.

While one might assume that the alumina housing fabrication was simple, it was not. NASA engineers designed it to support a network of channels with 52 heating elements allowing it to serve as an oven capable of reaching 1,000°C.

In an email interview with me, Walter Zimbeck, manager of TA&T’s Ceramic Micro Devices Group, described some of the details and considerations about making the oven housings via the stereolithography route:

What was the compelling reason for using stereolithography versus some alternative rapid prototyping technique?

Zimbeck: I never heard that they had found other ceramic rapid prototyping suppliers to bid on the parts, maybe back in the 2007 timeframe there were not any others. Goddard did have some prototypes made by plasma spraying alumina onto a mandrel and around pre-placed heating element wires, but apparently those prototypes failed during the first heating cycle (room temperature to ~1,000°C in several minutes). The ceramic cracked and the wires broke.

That’s a very challenging thermal shock event for any ceramic, so I was actually surprised that our fully dense high purity alumina housings showed no signs of degradation after the first, nor after many test cycles.  The NASA pyrolysis oven team was elated because they were on the hook to provide the ovens and had no other solutions.

The difficult part (why no conventional processes were viable) is the high aspect ratio holes that run the length of the cylinders.  The inner ring of holes have a 0.008″ diameter and are ~0.75″ long — an aspect ratio of almost 100! The outer ring is larger diameter (~0.002″).  The other challenging feature is the minimum wall thickness between holes and between the holes and inner & outer walls of the oven is 0.010″. Goddard was not able to find anyone who would bid the design using conventional ceramic machining, injection molding or extrusion plus machining.

Once the piece is initially formed via stereolithography, does it need to be sintered or modified in any way?

Yes, definitely.  When it comes out of the stereolithography machine it’s a green-state ceramic and must go through binder burnout and sintering, analogous to an injection-molded ceramic. The material we used for the ovens is a fine-grained, high-purity alumina that sinters very well to near theoretical density.

Prior to debinding, the parts also have to be cleaned of the uncured resin [which accumulates during the stereolithography process]. It turned out this required “good hand skills” to ensure the small holes were cleared. We initially used summer interns who were top-notch ceramic engineers from really good university material science programs, but they kept breaking the parts. We eventually assigned the detailing work to two technicians who were recent graduates of Maryland Institute College of Art in Baltimore. They had great hand skills and were very attentive to detail. They really made the process work. The [stereolithography] machine is a high-tech marvel that can make high-quality ceramic parts (relative to other additive manufacturing processes), but you still need good people to maintain that quality throughout the process.

How many of the heater housings did TA&T prepare?

We probably delivered 30 total parts over a year and half period from 2006–2008. There were two or three design iterations they made during that time, which is an advantage with ceramic stereolithography because it’s a tool-less process.

Overall, what’s the experience been like working on this project?

[NASA's] lead technician for the pyrolysis ovens came by our facility often since we are located less than an hour from Goddard. It was fun, we felt like we were part of the pyrolysis oven team, so when we Curiosity landed successfully, we were pretty excited—parts we made are on freakin’ Mars! Our excitement is amped up further now that we know the pyrolysis ovens are working and they may be essential to producing significant scientific findings.

I don’t mean to imply that the heater housing is the only ceramic-oriented component on Curiosity (if nothing else, the rover is filled with semiconductors). Further, many of the analytical components in the SAM system (and in Earth-based labs working to troubleshoot and confirm Curiosity’s findings) were contributed by companies familiar to ceramists and other materials scientists and engineers. For example, if the following brief video shows frequent glimpses of equipment made by Netzsch Analyzing and Testing:

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