GEARS QUARTERLY. Increasing the Performance of. Plus... Composite Airfield Matting. Hydraulic Fluid Contamination. YBCO Superconductors. and more!

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1 QUARTERLY Volume 7, Number Increasing the Performance of GEARS Plus... Composite Airfield Matting Hydraulic Fluid Contamination YBCO Superconductors and more! AMPTIAC is a DOD Information Analysis Center Administered by the Defense Information Systems Agency, Defense Technical Information Center and Operated by IIT Research Institute

2 You may have noticed that we are encouraging scratch that demanding that our readers verify their addresses in order to continue receiving this publication. We have asked this only once before in our six year history, and I promise you we will not do it again anytime soon. You all are familiar with the publications that swear this is the last issue you will ever get, unless you send in this card, or call this number. Well, I can tell you we aren t like that. This summer we are dropping anyone off our mailing list who does not specifically tell us they want to stay on it. This is not a passive event on your part, you must tell us that you want to stay on our list or you will be removed unceremoniously. Editorial: I Don t Want to Cut You... But I Will There are many publications out there that promise technical content, yet show up on your desk with advertisements, press releases, and other drivel not worth your valuable time. I certainly hope you do not include the AMPTIAC Quarterly in that category. We strive to bring you the exciting technology and developments of the Defense materials and processing community, and we do it in a neat and tidy package four times a year. You may have noticed also our switch to full color presentation last year, and our emphasis on larger, special issues devoted to specific areas of DOD technology. I can assure you we have a few more surprises up our sleeves but more on that in a minute. There are more than 23,000 Defense community professionals on our mailing list, and each one is mailed a free copy of every issue we print. Last year we distributed more than 100,000 copies of the Quarterly. As you can imagine, the cost of printing and distributing those issues is staggering, and we do not want any of those issues to wind up in the trash until after someone has read it. Maintaining a mailing list like ours is not easy, and frankly we need a little help from you. All we are asking is that you visit our website (the link is provided below) to verify that your current contact information is correct. You then click either Yes or No to whether you wish to continue receiving the Quarterly. We certainly hope you click Yes. And how about those surprises I mentioned? Well, for starters we are working with the Navy on a large issue for this summer on the materials and structures which are increasing Navy warship performance and capabilities. And we are in talks with the Air Force to present the latest in materials for space and propulsion applications this winter. But I don t want to let all of our secrets out of the bag, so if you want to see more of what we have in store you better verify your address and tell us to keep sending you the AMPTIAC Quarterly! All of us here at AMPTIAC certainly want to keep sending you the Quarterly, but you have to tell us that you want it. Please visit the web site below and click Yes. P.S. And as a reminder, we never share our mailing list with anyone. (Besides being just plain wrong, we are contractually required by the Government to protect our subscribers privacy.) Wade Babcock Editor in Chief About the cover: From gears to superconductor-levitated trains, this issue of the AMPTIAC Quarterly highlights some exciting advances in processing techniques and materials development. (Photography of gear manufacturing courtesy of Arrow Gear Company, Downers Grove, IL, Editor-in-Chief Wade G. Babcock Creative Director Cynthia Long Information Processing Judy E. Tallarino Patricia McQuinn Inquiry Services David J. Brumbaugh Product Sales Gina Nash Training Coordinator Christian E. Grethlein, P.E. The AMPTIAC Quarterly is published by the Advanced Materials and Processes Technology Information Analysis Center (AMPTIAC). AMPTIAC is a DOD sponsored Information Analysis Center, operated by IIT Research Institute and administratively managed by the Defense Information Systems Agency (DISA), Defense Technical Information Center (DTIC). The AMPTIAC Quarterly is distributed to more than 25,000 materials professionals around the world. Inquiries about AMPTIAC capabilities, products and services may be addressed to David H. Rose Director, AMPTIAC amptiac@alionscience.com URL: We welcome your input! To submit your related articles, photos, notices, or ideas for future issues, please contact: AMPTIAC ATTN: WADE G. BABCOCK 201 Mill Street Rome, New York PHONE: FAX: amptiac_news@alionscience.com

3 Benjamin Craig and Richard Lane AMPTIAC Technical Staff Rome, NY BACKGROUND The phenomenon of superconductivity is having a tremendous impact on the advancement of technology in many fields including medicine and electronics. It is expected to have more impact in the future of electric motors, power production and transmission, transportation and communication systems. Accordingly, the call to develop superconducting materials is strong and will remain so as the technology improves and becomes less expensive. Discovering or developing a material which becomes superconducting at room temperature is the ultimate challenge in superconductivity. But with the uncertainty of this ever being achieved, the current focus of much of the research, development and commercialization of superconductors, is on YBa 2 Cu 3 O 7-δ (often abbreviated YBCO or Y123 and where 0 δ 1; see also Figure 1). The reason so much effort has been put forth on researching and applying YBCO superconductors rather than alternative high-temperature superconductors (HTS) is because it has some of the best superconducting properties and offers the potential for lower cost products. Upon the discovery of superconducting properties in the YBCO ceramic at an exceptionally high critical temperature (T c ) of about 93 K in 1987, there was a flurry of research and development activity. This relatively high temperature, which is above the temperature at which nitrogen liquifies (77K), opened up the possibility for numerous advancements in electronic, magnetic, and related technologies. Prior to YBCO, all superconductors required costly liquid helium for cooling. HTS are a potentially revolutionary technology, especially for power generation, transmission, distribution, and storage. The potential energy savings are significant, as the reduction of energy losses over power transmission systems would result in a smaller amount of power needing to be generated to maintain equivalent levels of usage. This also results in a higher capacity available from existing generating plants, and an overall improved system reliability. Cleaner generating technologies such as wind and solar power would be made accessible to a wider population. YBCO has quickly become the most studied superconducting material, and through the evolution of its processing technology, it has also become one of the most frequently applied and commercialized as well. Although the application areas for superconductors are broad and range from microelectronics to transportation, only a small percentage of the potential applications have reached the commercialization stage. Even many of those are niche technology areas such as Brookhaven National Laboratory s particle accelerator. LEVITATION APPLICATIONS The levitation of objects as small as a simple permanent magnet (PM, as seen in Figure 2) or as large as a passenger train is possibly one of the most recognizable capabilities of superconductors. Superconductors produced in bulk form have a greater levitating capability than do superconducting films. They are usually placed in an array opposite an array of PMs, so as to produce a maximum levitating force. (Please see the accompanying sidebar Magnetic Levitation Explained for more details.) Bearing Systems Superconducting bearing systems could potentially yield virtually frictionless systems that require no lubrication. However, one of the biggest obstacles facing YBCO in this sort of levitation application is its low mechanical strength, which limits the maximum speed that can be achieved by the bearing system, since at high speeds the centrifugal force generated can be sufficient to cause severe mechanical failure.[1] Another obstacle facing superconducting bearing applications is fabricating a homogeneous superconducting material, where the levitating properties do not vary across the plane of the superconductor. The AMPTIAC Quarterly, Volume 7, Number 1 23

4 YBCO YBa 2 Cu 3 O 7-δ where 0 δ 1 Also abbreviated Y123 c = Å Oxygen Copper Yttrium Barium b = Å Figure 1. Crystal Structure of YBCO. a = Å Figure 2. Permanent Magnet Levitating Over a YBCO Pellet. (From the Consortium de Recherches pour L Emergence de Technologies Avancées, Lab. de Cristallographie, Centre National de la Recherche Scientifique, France; Reprinted with Permission) A derivative application of these superconductor-levitated bearing systems is an energy storage system using a flywheel. These systems, when compared to conventional bearings, can reduce power losses by a factor of 10, achieve diurnal storage efficiencies up to 90%, and store over 2 kwh of energy.[2] Maglev Trains Maglev trains have become one of the more admired applications in the levitation realm, primarily because of the concept of virtually no friction, which could lead to a highly efficient transportation system. Maglev trains have the ability to operate at much higher speeds (>300 mph) than wheel-based trains, while maintaining safety and reliability, and ultimately providing a much-needed alternative to air travel. Although there are a number of maglev projects underway around the United States, the technology remains mostly in the development and testing stage. The first maglev train in the US has recently been placed on its tracks at Old Dominion University in Virginia. Even though the ODU train and several other current projects use copper wound electromagnets rather than superconductors for the levitation force, it is an important step toward developing and implementing the levitation technology as well as gaining support and funding for future projects. Many of these future projects will use the more advantageous superconductor technology when it is fully developed. The Japanese have been researching, developing and testing maglev trains that employ low-temperature superconductors (LTS; with T c s which are much lower than 77K) for a number of years. (See Figure 3) Superconducting maglev technology is also being used for Superconductor Definition and Mechanism Many materials exhibit a traditional electrical resistance behavior above some critical temperature, and superconductivity below that temperature. For most materials however, this critical temperature is very near absolute zero. As the material s temperature approaches this critical value (T c ), the material becomes less resistive, until it finally exhibits a complete disappearance of electrical resistance upon reaching T c. Materials in the superconductive state conduct electricity perfectly, or without resistance. Resistance T c Temperature SUPERCONDUCTOR PROPERTIES There are three properties that are important to understand when discussing superconductor materials. One is the critical temperature (T c ) below which a superconductor reaches zero resistance, and above which the material is in a normally resistive state. (The current world record holder is an HgTlBaCaCuO compound with a T c of 138 K at ambient pressure.) The second property is the critical current density (J c ) which indicates the maximum current that a superconductor can carry without destroying its superconductive state. Finally, the critical magnetic field (H c ) is the maximum magnetic field a superconducting material can tolerate. Higher magnetic fields result in a reversion to the normal conducting state. 24 The AMPTIAC Quarterly, Volume 7, Number 1

5 national defense efforts in an upgrade to the High Speed Test Track operated by the 846th Test Squadron at Holloman AFB. It will employ a maglev system to achieve a Mach 9 ground test capability, and will assist NASA in establishing the requirements and understanding the potential for launch assist programs. ELECTRIC POWER APPLICATIONS Wires/Tapes The first and most obvious use for the first HTS was distribution of electricity. Just replacing current copper cables with an HTS will result in power savings of approximately 7%.[3] While this may not sound like much, a 7% drop in power production implemented on a large scale easily results in billions of dollars saved. Moreover, additional power to the consumer will be immediately available, thus reducing the need to construct new power plants to meet increasing demands. Replacing wiring in motors, generators and transformers will increase the savings to 8% or better. To make this savings possible, however, fabrication of the HTS cables would have to be the same cost as copper cables, which has not been achieved. The goal set forth is to lower the cost of HTS wires to $10/kA-m making them desirable for widespread use (copper is about $4/kA-m). YBCO offers the potential to operate in high magnetic fields at temperatures above 77 K and obtain the cost/performance goal if a low cost continuous fabrication method can be developed. Current continuously-produced YBCO wires/tapes are a maximum of about 1 meter long.[4] Cost/performance projections suggest a continuous YBCO wire will run $30 to $50/kA-m (depending on operating temperature) by 2005, with at least a four fold decrease by 2010.[5] Superconducting Magnetic Energy Storage (SMES) SMES is a type of uninterruptible power source (UPS) which provides energy backup to critical systems in case of a power interruption, reduction or loss. A superconducting coil stores a significant amount of energy that can be used when the main power supply fails. SMES has a high storage capacity, can boost power output, is very reliable, and can respond very quickly to any sort of disturbance that requires its use. Several 1 MW units are currently in use providing quality power control to facilities around the world. Figure 3. Japan s Maglev Train. (Reprinted with Permission of Central Japan Railway Company) Electromotors Melt-textured[6] YBCO is used for the rotor components to create high power density electromotors.[1] Electromotors employing this superconducting technology can generate a power density approximately eight times higher than conventional motors. They also have many advantages over conventional motors, including increased horsepower and efficiency, as well as reduced size (shown in Figure 4), weight, Superconductors are inherently perfect diamagnetic materials, which completely shield applied magnetic fields from penetrating the superconducting material. In the simplest case, when a permanent magnet (PM) is placed over Permanent Magnet a superconductor, the magnetic field produced by the PM is repelled by an equal and opposite Superconductor field produced by the superconductor. This causes the PM to levitate above the superconductor. In the same way, electromagnets can be used to levitate superconducting magnets. Non-Superconducting State Superconducting maglev trains are based on this concept of diamagnetism. Magnetic Flux is Indicated by Colored Lines = Flux of PM = Induced Flux in Superconductor Magnetic Levitation Explained Superconducting State The AMPTIAC Quarterly, Volume 7, Number 1 25

6 Figure 4. Conventional Motor (Left) and an HTS Electromotor (Middle). Internal View of an HTS Electromotor (Right). (Reprinted with Permission of American Superconductor) noise, cost and pollution.[7] These motors are potentially capable of providing a dramatic increase in efficiency over conventional motors used to operate industrial pumps, fans, belt drives, and compressors. The US Navy is interested in HTS motors for ship propulsion. Although the 20,000 hp and 35,000 hp motors required for electric war-, cruise- and cargo-ships are not yet attainable, there has been significant progress toward this level of power. A 5000-horsepower motor has already been built and tested, with 6500-hp AC synchronous motors in development for delivery in the summer of 2003.[8] The HTS propulsion electromotors are designed to significantly reduce the size and weight of conventional propulsion motors with the same power output, thereby increasing fuel efficiency and creating more space for cargo and equipment. The expected world market for motors utilizing superconducting technology is approximately $400 million per year and is projected to grow to $2-4 billion per year within ten years. Fault Current Limiters Superconductors have characteristics that make them inherently good fault-current limiters, which protect against power surges. That is, they can go from a superconducting state to a resistive state by simply increasing the current beyond their critical current level (J c ), which is the point at which their superconductive behavior breaks down. For this particular application, the superconductor can detect a surge, undergo a change in its conductive state, absorb the surge of energy, and return to its original state once the disturbance has been eliminated. While costs are still high for superconductor-based fault current limiters primarily due to material fabrication, the potential improvements over conventional limiters motivate their development. The advantages of superconducting fault current limiters are numerous and they include improved safety, reliability, power quality, flexibility, maintainability, and operating capacity, as well as reduced fault current levels and standby energy losses.[7] For instance, a typical transformer sees fault current levels up to times the steady state current, but a superconducting fault current limiter can reduce this level to three-to-five-times steady state. Second stage testing has been performed on 15 kv superconductor fault current limiters. Communications Filters Wireless networks are rapidly growing throughout the world, and their increased use will cause an increase in data traffic and thus significantly increase the amount of interference. A perfect filter would be able to completely screen out noise without cutting any of the desired signal, and filters utilizing YBCO superconducting technology can almost attain this. Aside from improving the quality of the signal by reducing the noise, the communications bandwidth can be increased by 30 to 80% and the transmit power needed for the signal can be reduced. YBCO superconducting filters provide the further advantage of increased sensitivity (the result of noise reduction) which can expand the range over which the wireless technology can be used. A practical advantage of superconducting filters over conventional filters installed in base stations is that they have a dramatically reduced size and weight.[9] It has been reported that the market for superconducting filters is estimated to grow to $8 billion over the next five years.[10] Superconducting Quantum Interference Device The superconducting quantum interference device, or SQUID, is extremely sensitive to magnetic fields. These electronic devices are based on the Josephson effect, which is the tunneling of electrons from one superconductor (S) layer, through a Contacts Superconductor Figure 5. SQUID SNS Junction. N-layer Insulator 26 The AMPTIAC Quarterly, Volume 7, Number 1

7 negatively charged (N-type)-non-superconducting material, to another superconductor layer. This creates an SNS junction as shown in Figure 5. The use of YBCO for SQUIDs instead of typical low temperature superconductors gives several advantages, including a less complex apparatus, increased flexibility and mobility, and reduced cost. Magnetic sensing devices with tremendous sensitivity can be used for various purposes, like geological and astronomical observation. The United States military has employed this technology to locate mines and submarines. Having the greatest magnetic sensing capability of any device, SQUIDs will have many other functions as well. Magnetic Resonance Imaging/Nuclear Magnetic Resonance Superconductors play a major role in magnetic resonance technology, which has a huge market with magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) spectrometers. Magnetic resonance, which relies on powerful magnets, originally utilized very expensive electromagnets or very large and heavy permanent magnets, thus allowing only limited access to these systems. The development of low-temperature superconductors led to a vast improvement in machine size, weight, image quality and ultimately availability to a variety of medical facilities, but the cost of cooling the superconducting magnets is still high. The development of YBCO superconductors is a big step for this technology mainly because they do not require the expensive liquid helium cooling systems. With the development of HTS, magnetic resonance systems can become more widely available at lower costs, while providing great improvements in sensitivity, quality, and observational time compared to the conventional low-field copper coil, heavy permanent magnet and LTS systems.[11] NOVEL PROCESSING METHODS The downfalls of YBCO are its inherent brittleness and the difficulties in producing the superconducting phase. YBCO is a ceramic material and is therefore highly susceptible to cracking and fracture. The best method found thus far to improve the mechanical properties of YBCO without significant degradation in its superconducting properties, is to add silver. Silver does not react with YBCO and forms particulates primarily at the grain boundaries, thus decreasing grain boundary resistivity and increasing the critical current density. The addition of Ag however, adds another level of complexity to a technology where reducing costs is a major driving force. The second major hurdle has been the high processing temperature required to produce the superconducting phase, hindering thin film fabrication. High temperatures cause diffusion between the YBCO layer and the substrate, degrading the superconducting properties. Substrate materials must therefore be selected which react very little if at all with YBCO. Grain alignment is also very important in YBCO to produce the highest J c materials. This is achieved by depositing YBCO epitaxially onto lattice-matched substrates. Substrate selection becomes even more critical as thermal expansion characteristics must match closely to limit stresses, and a low dielectric constant in high frequency applications is also desirable. Materials identified that best fit these qualifications are, not surprisingly, ceramics similar to YBCO. Therefore, in order to produce functional thin film devices, tailored ceramic substrates are used as buffer layer(s) between the YBCO film and a primary substrate material. In the past, problems associated with processing YBCO superconductors have resulted in unique fabrication methods developed for both bulk materials and thin films. Existing processing techniques were modified to increase the oxygen content during YBCO growth and promote grain alignment. Ex-situ processing methods are generally used for bulk materials and thick film depositions. This approach requires a post anneal at high temperatures to produce the superconducting phase and results in materials with a low J c. The advantages of ex-situ processes are that they are low cost, can be scaled up for commercialization, and can be used to coat intricate shapes. In-situ deposition methods are used to fabricate high J c thin films on lattice-matched substrates eliminating the post anneal process. Pulsed laser deposition (PLD) has become the preferred deposition method, although there are several others capable of producing in-situ YBCO superconducting thin films. In-situ processing techniques are generally high cost, with continuous large-scale fabrication a difficult task. Figure 6. Multilayer YBCO Wire Technology. Silver Contact YBCO SmBCO CeO 2 IBAD YSZ Nickel Alloy Melt Processing Melt-texturing is a method to optimize grain alignment in YBCO bulk materials. This technique can produce YBCO disks with a J c of 10 4 to 10 5 A/cm 2 under a magnetic field of up to 3 T.[12] Liquid-phase removal is a more specific melttexturing technique that can achieve a J c of about 10 4 A/cm 2, and does not require seeding.[12] The advantages of this technique are that it is simple, a rapid growth rate is achieved, and it is a good method for creating materials with high aspect ratios. Seeded growth, on the other hand, is a process that uses a seed crystal on which to grow a single-domain superconductor with a well-defined orientation. Although melt texturing has provided some significant advancements in bulk processing of YBCO superconductors, there are some issues left to be addressed, including improving superconducting and mechanical properties, and increasing the growth rate of the grains for large-scale production.[12] Ion Beam Assisted Deposition Ion Beam Assisted Deposition (IBAD) is used to create textured substrate materials for the epitaxial deposition of YBCO. To create Josephson junction devices, biaxially textured yttria The AMPTIAC Quarterly, Volume 7, Number 1 27

8 stabilized zirconia (YSZ) is deposited on silicon using IBAD, followed by epitaxial deposition of CeO 2 and YBCO by PLD. Conventional photolithography can then be used to pattern the layered material into an electronic device. IBAD is also under research at Los Alamos National Laboratory for the development of YBCO wire technologies. Like the Josephson junctions, YSZ is deposited via IBAD, but for wire applications the primary substrate is a nickel alloy. The nickel alloy is used for its ductility producing a flexible wire. PLD is then used to produce the subsequent layers of CeO 2, SmBCO, and YBCO. The multilayer approach, seen in Figure 6, helps to maintain higher J c levels with increasing wire thicknesses. E-beam Evaporator Substrate Normal Oxide Vapor Flux α Nickel Substrate Bi-axially Textured Oxide Crystals Inclined Substrate Deposition A second method to create a biaxially textured substrate for YBCO superconducting thin films is referred to as the inclined substrate deposition (ISD) process. (See Figure 7.) A nickel alloy substrate is mounted at a specific angle with respect to the oxide vapor flux from an e-beam evaporator. With the proper angle of inclination, a bi-axially textured buffer layer oxide (such as MgO) may be deposited across the nickel surface. YBCO is then deposited on the buffer oxide using PLD or metalorganic chemical vapor deposition. The process can produce deposition rates up to 100 Å/sec, making it better suited for production. Research and development efforts on YBCO wire technology using ISD are currently underway at Argonne National Laboratory. Figure 7. Graphical Depiction of the Inclined Substrate Deposition Process, where the Oxide Vapor Flux Encounters the Substrate at an Off-axis Angle α. and more reliable electrical systems, significant energy savings, lower pollution, safe high-speed transportation, relatively inexpensive and widely available MRI, and more robust and capable wireless communication systems are just some of the advances made possible by superconducting materials. Until room temperature superconductors are developed, or until cheaper and more capable superconducting materials can be made, YBCO will remain the material of choice for many current superconductor applications. Rolling-assisted Biaxially Textured Substrates The rolling-assisted biaxially textured substrates (RABiTS) technique was developed at Oak Ridge National Laboratory and is a third method of producing a textured substrate for YBCO. This method is specific to wire fabrication. A biaxially textured nickel substrate is formed by cold rolling, followed by a heat treatment causing recrystallization.[13] The buffer layer(s) and the YBCO layer can then be deposited using PLD. CONCLUSION Since its discovery in 1987, steady advancements have been made in developing YBCO superconductor technology, but difficulties with processing and fabricating YBCO parts are inhibiting its widespread application and commercialization. The continuing successes in material development and novel processing techniques to overcome these difficulties (for instance coated conductors and melt-texturing) suggest a promising future for YBCO. Many exciting and potentially revolutionary applications that may be capable of changing our day-to-day lives dramatically have been envisioned. Many of these applications simply await the maturation of superconductor technology (with higher temperature performance and lower costs), while some are already being commercialized and implemented in various systems and locales around the world. Improved power service REFERENCES [1] T. Habisreuther, M. Zeisberger, D. Litzkendorf, O. Surzhenko, and W. Gawalek, Developing Melt-Textured YBCO, JOM, The Minerals, Metals, & Materials Society, Vol. 52, No. 6, June 2000, pp [2] J.R. Hull, Using High-Temperature Superconductors for Levitation Applications, JOM, The Minerals, Metals, & Materials Society, Vol. 51, No. 7, July 1999, pp [3] O. Port, Moving More Juice through the Wires: Superconductivity Could Shave Billions off Energy Bills, Science and Technology, February 2002 [4] T. G. Holesinger, S.R. Foltyn, P.N. Arendt, H. Kung, Q.X. Jia, R.M. Dickerson, P.C. Dowden, R.F. DePaula, J.R. Groves, and J.Y. Coulter, The Microstructure of Continuously Processed YBa 2 Cu 3 O 7 Coated Conductors with Underlying CeO 2 and Ion-Beam Assisted Yttria-Stabilized Zirconia Buffer Layers, Journal of Materials Research, Vol. 15, No. 5, 2000, pp [5] Accelerated Coated Conductor Initiative, prepared by Energetics, Inc. for the DOE, superconductivity/pdfs/acci_to_print.pdf [6] The organization of the crystallography in a material is called texture. Texturing a material is the act of organizing its crystallography in a desired fashion [7] C. Cox and R. Hawsey, The Potential of Super- 28 The AMPTIAC Quarterly, Volume 7, Number 1

9 conductivity, Energy Magazine, Business Communications Company, Inc., Winter Also available at _supercon.pdf [8] American Superconductor Announces US Navy Contract to Create World s First HTS Ship Propulsion Motor, American Superconductor Press Release, February 20, 2002, [9] R. Simon, Conductus Technology: An Enabling Technology for Advanced Wireless Networks?, Conductus.com/pdf/whitepaper_Rsimon_ pdf [10] J. Flanigan, Superconducting Filter Firms Get Hot, Los Angeles Times Syndicate, February 18, Available at flanigan/ [11] J.A. Schofield, Super-Conductors Lower Design Costs, Design News, June 9, 1997 [12] W. Lo, Recent Progress in Large-Grain REBCO Melt Texturing, JOM, The Minerals, Metals & Materials Society, Vol. 52, No. 6, June 2000, pp [13] M. Paranthaman, C. Park, X. Cui, A. Goyal, D.F. Lee, P.M. Martin, T.G. Chirayil, D.T. Verebelyi, D.P. Norton, D.K. Christen, and D.M. Kroeger, YBa 2 Cu 3 O 7-y Coated Conductors with High Engineering Current Density, Journal of Materials Research, Vol. 15, No. 12, 2000, pp PRESENTATION OF THE JOHN W. LINCOLN AWARD Mr. Royce Forman, Senior Scientist of the Structural Engineering Division, NASA Johnson Space Center, Houston, Texas, was presented the 2002 John W. Lincoln Award. It was given in recognition of his outstanding work over many years in advancing the technology associated with the concept of aircraft structural integrity. The Award was presented at the 2002 USAF Aircraft Structural Integrity Program (ASIP) Conference in Savannah Georgia on 10 December The Award, which consists of a gold medal and a certificate of recognition, was named in honor of the late Dr. John W. (Jack) Lincoln of the Aeronautical Systems Center, Wright-Patterson Air Force Base, Ohio. Dr. Lincoln was a pioneer and major contributor to the development and application of durability and damage tolerance design to ensure the safety and longevity of both military and commercial aircraft. The Award has been presented previously to: Dr. Lincoln (1996) Mr. Charles Tiffany (1997) Mr. Thomas Swift (1998) Professor Jaap Schijve (1999) Professor Alten F. Grandt, Jr. (2000) Dr. James C. Newman, Jr. (2001) A plaque with the names of the recipients is on display at Wright-Patterson Air Force Base, Ohio. The AMPTIAC Quarterly, Volume 7, Number 1 29