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“Atoms to armor” —Army invests in basic research to design new materials will help in the prediction of performance or properties. Two-year goals: Science: Advance the experimental and computational state-of-the-art for characterizing the in-situ materials response to extreme dynamic environments at critical length and time scales in metallic, polymeric, ceramic, and composite material systems. Benefit to the soldier: Improved protection systems through incorporation of enhanced discrete deformation and failure algorithms in current continuum simulations and design codes. Five-year goals: Science: Integration of novel experimental methodologies and multiscale computational approaches to enable unprecedented microstructural control and predictive capabilities. Benefit to the soldier: The CRA will transition to the Army and the industrial base the key materials characteristics and properties to achieve a 15–30 percent weight reduction for selected protection systems. Ten-year goals: Science: Demonstrate a comprehensive “materials-by-design” capability to include designing materials and predicting key properties for materials in extreme dynamic environments. Benefit to the soldier: The CRA (including ARL) and industrial partners will utilize the “materials by design”capability to design and produce protection materials with one-third the weight of the current systems. Q. The University of Utah MSME coalition focuses on lighter, more efficient electronic devices and batteries. What are some examples of field applications? A. The development of lightweight, field-adaptable power and energy is one of our highest priorities. The intent is for the multiscale models to be developed by the MSME university team that will advance the fundamental science, understanding, and state-ofthe art for multiscale, multidisciplinary What are“Materials by design?” “‘Materials by design,’ conceptually, describes a process of designing materials from the atomic to the macroscopic scale for a particular suite of mechanisms and properties that are required for defined performance/applications. Very simply, it is not how to design components (systems) with existing materials, but how to select and design materials for defined applications,” says Jim McCauley of the Army Research Laboratory. The idea was first formalized by Michael Ashby, a professor at Cambridge McCauley holding boron carbide personnel University (UK) with his classic 1992 armor insert manufactured by Ceradyne (now work, “Materials Selection in Mechanical owned by 3M Company) with two faintly Design.”3 In it, he introduced the concept visible projectile strikes. of a “material index,” or “figure of merit,” which characterizes the performance of a material in a given application. For example, plots of Young’s modulus against density for many materials reveal groupings. Today, people talk about designing materials for the “Ashby white space”—regions of the plot where no known materials have the combined material index. Northwestern University professor Gregory Olson (who coined the “materials by design” phrase), added the use of computational methods in his 1997 seminal paper, “Computational Design of Hierarchically Structured Materials,” which introduced the importance of multiple scales and the interrelationships between processing, structure, properties, and performance.4 In 1997, DOD’s director of defense research and engineering, Anita Jones, issued a challenge to the department’s scientists and engineers to adopt advanced materials design and the evolving computational tools to optimize armor materials. The Army responded to the “atoms to armor” call to action with a new strategic research objective (Credit: Joyce Conant, ARL.) (SRO) initiative in 1997/1998 called “Armor Materials by Design,” which was submitted by McCauley, G. Hagnauer, and T. Wright. However, at the time, the computational science was unable to support the vision of the SRO, especially with regard to the complexity required for highstress high-strain-rate situations. A series of workshops, conferences, and papers in the early 2000s addressed the gaps and gained broad support for the SRO’s vision, culminating in a seminal workshop held in Townson, Md., in 2008. About the same time, several other reports published similar recommendations, including a 2008 National Academies study, that formalized the phrase “integrated computational materials engineering.” 2 The National Research Council’s National Materials and Manufacturing Board and the Board of Army Science and Technology recommended DOD establish a basic and applied research initiative for protection materials by design and that it include a combination of computational, experimental, and materials testing, characterization, and processing research conducted by government, industry, and academia.1 And, thus, was born the Enterprise for Multiscale Research of Materials. n models in the electronic materials research areas I mentioned before: electrochemical energy devices; hybrid photonic devices; and heterogeneous metamorphic electronics. The experimentation for validation and verification for these models will be performed by ARL scientists in each of the three electronic materials research areas, which is expected to be part of a continual process to improve and create new models through collaboration. In the area of electrochemical energy devices, the CRA will look at lithiumion batteries and alkaline-membrane fuel cells. The hybrid photonic devices thrust includes material modeling for multispectral detectors (III–nitride alloys); material modeling for light emitters; defects, interfaces, and dislocation studies (GaN and AlGaN); and plasmonics and metamaterials 30 www.ceramics.org | American Ceramic Society Bulletin, Vol. 92, No. 2


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