1. Directions and Opportunities in DARPA's Materials Program 2. This chart retells the synergism of DSO’s program with an emphasis on materials. The program to be described in this talk is primarily focused on Materials and Devices. However, there are also synergies with the other elements. 3. This chart covers the bulk of the materials program. Examples of each of these thrusts, as well as, new opportunities will form the basis of the talk. This chart is included primarily as a reference, especially to note the program managers who are responsible for the area. Dr. Warren will present the Mesoscopic Machines program. 4. In addition to the major thrusts to be described in this talk, there are several related efforts in other areas. For example, the biomimetics work described in Dr. Rudolph’s talk depends heavily on materials to effect the structures he described. In addition, the DSO mathematics program has a strong interaction with the materials program. This includes the Virtual Integrated Prototyping Program that is using advanced mathematics to model thin film materials processing. 5. Before any specific programs are described, it is useful to provide a brief overview of the philosophy that guides DARPA’s materials research program. Because the research is not aimed at solving near term problems, it is by design, focused on those emerging defense needs for which new materials and new materials capabilities are likely to be enabling. This is accomplished by exploiting new concepts in materials science as shown. 6. This first chart shows one of the better examples of how DARPA’s materials research program is exploiting new approaches to enable new capabilities here in the area of personnel protection. The goal of this program is to drastically reduce the weight of body armor in order to significantly increase the survivability and mobility of the soldier. The only way that such a reduction can be accomplished is by changing the way in which body armor is designed, including the exploitation of new mechanisms. This means that traditional shoot and look methods must be replaced by model and test. An example of the payoff in looking anew at an old technology is shown on this chart. Here the effect of the stiffness of the second layer is examined using modeling substantiated by testing. The surprising result is that one wants a very stiff layer under the ceramic, versus the flexible composite currently used to back the hard first layer 7. As shown on this slide, the design of materials, especially for multi-functionality, could have a huge payoff. The example shows how one can apply the unique porous microstructure of ultra-lightweight metals to a structure that has channels for cooling or even sensing. Other applications such as structures for blast mitigation are also possible. This is an area that DARPA is interested in pursuing. 8. This is an area that DARPA has been involved in for several years and shows promise to revolutionize the way structures are put together. In fact, it is the precursor to other multi-functional materials. This chart shows the various materials that have been examined and lists some of the on-going demonstrations. 9. In a similar vein, electroactive polymers are in a sense, intrinsically smart materials. DARPA’s interest is exploiting both their electroactive properties and their structural properties. 10. This chart depicts the use of electroactive polymers as the holy grail for actuation – that of emulating human muscle. Other advantages might include micro-actuation, such as on the scale of MEMs. 11. This chart shows two other applications for Electroactive polymers, both with the potential to make significant changes in Defense capability. On the left is depicted the use of conducting polymer to provide analog processing similar to that performed by the human eye at speeds up to 10 times faster than digital. On the right is an example of the use of these polymer as light emitting elements – beginning along the path to a truly flexible display. 12. Though smart materials and structures is a technology with a large potential, such potential might not be reached unless one learns to design with these materials. Thus, system level, concurrent design will be a critical part of the smart materials equation. 13. The development of power sources for Defense systems, especially for the solider, is among the most critical technologies required by DoD. Unfortunately, time permits only a small discussion of this large and important effort. This chart shows how the critical issues in power generation depends on materials. 14. As part of this effort, novel approaches for generating small scale power are being undertaken. Here are examples of the world’s smallest gas turbines. While the performance of this turbine is incredible, it will be enhanced by the use of ceramics produced by solid free-form technology, a processing approach pioneered by DARPA. In the future, button sized turbines have the potential to outperform (on a weight basis) even this small, hand sized power generator. 15. Another materials development that could change the way power is generated is in the development of high power, permanent magnets. Increasing the magnetic energy product, the mechanical strength, and the use temperature opens up entirely new capabilities in the design and application of motors. 16. Finally, DARPA is examining ways to extract energy from the environment to provide the power for the soldier and for devices such as unattended ground sensors. Approaches range from traditional photovoltaics to garnering the energy from the heel strike of a soldier. 17. Depicts approaches for gathering energy from a soldier’s heel strike. 18. Now, a bit more speculative. With the development of a range of smart materials and actuator concepts and work on power generation, it seems only natural that one consider how such technology could be combined to enhance the warfighter’s capability. This chart shows a notional example. 19. As described earlier, DARPA attempts to make significant changes in the way materials are used. Spintronics is one of the best example of that. While the traditional approach to electronics uses charges, DARPA has pioneered the field of “Spintronics” that, as the name implies, uses the spin of electrons rather than their charge to perform electronics. This chart depicts Giant Magneto Resistance (GMR) using spin transfer. 20. DARPA has already made great promise in exploiting spins to produce non-volatile, rad-hard memory as shown on this chart. 21. However, recent discoveries on the stability of coherent spins in semiconductors can lead to even more revolutionary breakthroughs in functional materials as shown on this chart. 22. Just like spintronics, another approach for revolutionizing functional materials is molecular electronics. This concept relies on electronic changes in molecules to perform functions now relegated to areas of semiconductor surfaces. If such technology could be made 3D, one would then ask how many Pentium chips could one put on the head of a pin. However, one aspect of such molecular based circuits is that they would have to be fault tolerant. One might also think of using biologically derived molecules to achieve similar performance. 23. This chart graphically depicts the broad subject of nano-technology. As can be seen from many of the topics preceding, the control of microstructure at the nano-size range, even for macroscopic materials, can lead to exciting new properties. The key for DARPA is to associate these interesting structures with specific advantages in their properties. 24. Clearly at this meeting, you have heard and will continue to hear about a variety of interesting structures and devices. It should become obvious that the most significant payoff is achieved when one integrates these together. The challenge here is that, while work is being done at individual scales, no one is yet taking up the gauntlet to develop technologies that can bridge the size and function gap. 25. Another challenge to the materials community is to find ways to accelerate the discovery of new materials more quickly and at the lowest cost possible. Combinatorial synthesis is one such way. This chart shows the basic concept for combinatorial synthesis. 26. On this chart, one sees the potential for combinatorial synthesis in the development of thermoelectric materials. Note that since DARPA began to look at advances in thermoelectrics, great progress has been made in improving existing materials and concepts. However, the promise of combinatorial synthesis is that one can find complex material systems rapidly – with the potential to outperform years of traditional research. 27. Finally, the last challenge is an overarching one in materials science. After one has developed a material, how does it cross the fence to the design community and get used. Traditionally it takes 15 or more years for a material to find its way into a system or device. In this regard the electronics industry is not much better than more traditional industries such as aerospace. 28. One possible solution to this dilemma is to develop approaches to assure that materials R&D leads not just to interesting technology, but directly to a “database” that designers can use. 29. Finally, this chart summarizes the existing and potential opportunities in the DARPA materials sciences program.