1.1 Materials Science Division

The objective of research supported by the Materials Science Division of the Army Research Office (ARO) is to realize unprecedented materials properties via discovery of the fundamental relationships that link chemical composition, microstructure, processing history, and material properties. The work, although basic in nature, is focused on developing new materials, material processes, and properties that promise to significantly improve the performance, increase the reliability, or reduce the cost of future Army systems. With the need for lighter weight and higher performance systems in the future, program emphasis has increasingly shifted away from metals research to a more balanced program with interests that cross a broad spectrum of materials including polymers, ceramics, and semiconductor materials. Fundamental research that lays the foundation for the design and manufacture of multi-component systems such as composites, hierarchical materials, and "smart materials" is of particular interest. Other important areas of interest include new approaches for materials processing, new composite formulations, surface treatments that minimize environmental impacts, and novel composite concepts including multifunctional and hierarchical materials. Finally, there is general interest in identifying basic research in the area of manufacturing science which will address fundamental issues related to the reliability and cost (including environmental) associated with the production and long-term operation of Army systems. The following areas of research are not intended to reflect all of the activities of the Materials Science Division because there is always interest in new ideas and cross-disciplinary concepts in materials science that may have future applications for the Army.

1.1.1. Materials Design

The objective of the Materials Design program is to tailor material properties for application-driven property requirements. The research should investigate property interrelationships in materials growth, processing or characterization with the approach eventually leading to stronger coupling of experimental research with theory or modeling (including phenomenological modeling). The goal is to predict and control material behavior during processing and operation, to predict property changes over time (based on science rather than statistics), to optimize performance and reliability, and to reduce cost and time for development. It would also be advantageous to develop strategies to define constraints imposed by the experiment and theory, and to establish and populate open databases for processing microstructure properties performance etc. These strategies could be continually updated to enable design, simulation, modeling, and theory to evolve and ultimately for property tradeoff in support of optimum performance to occur. In addition, this should also facilitate communication among researchers and engineers at the materials, subsystem, and system level. One area of emphasis will be surface and interface engineering in support of materials integration. There is particular interest in identifying new ways of combining similar and dissimilar materials which provide multifunctional capabilities, recognizing that functionality is often derived from properties very close to the interface. Processing models that build a solid theoretical underpinning will be a key to control/optimization of surface and interface properties. Surface and interface research in areas such as organic/semiconductor, bio/semiconductor, or bio/organic/semiconductor interfaces; dielectrics/semiconductor interfaces; transparent conductive thin films; dissimilar material and nano-electrical contacts; and bonded or alternative substrates can be envisioned. Another area of emphasis will be development of in-situ and ex-situ analytical methods for analysis over the appropriate dimensions, that is, methods with appropriate spatial resolution or appropriate sensitivity. The goal is to understand and control material and growth parameters that affect a desired or undesired property within a particular property range. Other areas of interest are investigations of high temperature materials and their relevant degradation modes; development of adaptive materials capable of response to internal or external stimuli; study of self-repair or self-healing effects; growth and characterization of embedded nano-sized constituents designed for material and performance health monitoring; and investigations of novel methods leading to large-scale, large-quantity processing of nano-materials. It is intended that in addition to promoting convergence; combination and integration of similar and dissimilar materials the program also promotes convergence of and cross-disciplinary concepts for materials design.

Technical Point of Contact: Dr. John T. Prater; e-mail: John.T.Prater@us.army.mil; (919) 549-4325.

1.1.2. Mechanical Behavior of Materials

The Mechanical Behavior of Materials program seeks to establish the fundamental relationships between the structure of materials and their mechanical properties as influenced by composition, processing, environment, and loading conditions. The program emphasizes research to develop innovative new materials with unprecedented mechanical and other complementary properties. Critical to these efforts is the need for new materials in science theory that will enable robust predictive computational tools for the analysis and design of materials subjected to a wide range of specific loading conditions, particularly theory which departs from standard computer algorithms which is not dependent upon tremendous computational facilities. The primary research thrust areas of this program include: 1) high strain-rate phenomena (e.g., experimental and computational analysis of the physical mechanisms which govern deformation in advanced materials, lightweight damage tolerant materials); 2) property-focused processing (e.g., materials science theory to predict the range of properties attainable with advanced processing methods, novel approaches for enhancing specific toughness); and 3) tailored functionality (e.g., innovative materials containing unique and specifically designed chemical and biological functionalities and activities while maintaining, or preferably enhancing, requisite mechanical properties). Additionally, of joint interest with the Polymer Chemistry program in Chemical Sciences are research efforts seeking to generate statistically valid bulk mechanical behavior data with small polymer samples. In all cases, three to four page white papers describing a specific research objective, scientific approach, and anticipated scientific impact are encouraged to initiate a discussion of potential research directions.

Technical Point of Contact: Dr. David Stepp, e-mail: David.M.Stepp@us.army.mil , (919) 549-4329.

1.1.3. Synthesis and Processing of Materials

The program on Synthesis and Processing of Materials focuses on the use of innovative approaches for processing high performance structural materials reliably and at a lower cost. Emphasis is placed on the design and fabrication of new materials with specific microstructure, constitution, and properties. Research interest includes experimental and theoretical modeling studies to understand the influence of fundamental parameters on phase formation, micro structural evolution and resulting properties in order to predict and control materials structures at all scales ranging from atomic dimensions to macroscopic levels. Trends in this subfield include non-equilibrium materials processing (e.g., rapid solidification); powder synthesis and consolidation; novel processing of ceramics, polymers, metals, and composites; welding and joining including composite materials; elastomers; fibers and fabrics; and utilization of micro structural, compositional, or other unique signatures which may provide non-destructive in situ feedback process control to enhance a product's reproducibility and quality. Supercritical fluid, shock-induced chemical processing and other innovative approaches for processing materials are also of interest.

Technical Point of Contact: Dr. David Stepp, e-mail: David.M.Stepp@us.army.mil , (919) 549-4286.

1.1.4. Physical Behavior of Materials

The Physical Behavior of Materials program seeks research directed at providing an improved understanding of the fundamental mechanisms and key materials and processing variables that determine the electronic, magnetic, and optical (EMO) properties of materials that affect the reliability of EMO devices. Emphasis is on research that will facilitate the nano-structuring of materials to realize the materials-by-design concept where new and unique materials are constructed on the atomic scale with application-specific properties. This includes research on understanding the underlying thermodynamic and kinetic principles that control the evolution of microstructures; understanding the mechanisms whereby the microstructure affects the physical properties of materials; and developing insight and methodologies for the beneficial utilization and manipulation of defects and microstructure to improve material performance. Major trends in this subfield include: 1) electronic materials - materials for microelectronics and packaging; fabrication and processing of semi-conductors, interconnects and device structures, and the characterization and control of trace impurities, defects and interfaces in semiconductors, 2) magnetic materials - bulk and thin-film processing of magnetic materials for electronic and high frequency communications; and fundamental studies on magnetic coercivity and spin dynamics, and 3) optical materials - materials and processing methods for detectors, lasers, nonlinear optical materials, refractive and diffractive optics, and optical windows and coatings. Research to improve the long-term stability of EMO materials, develop multifunctional or smart EMO materials, and develop low observable materials is also being sought.

Technical Point of Contact: Dr. John Prater, e-mail: John.T.Prater@us.army.mil (919) 549-4259.