should be expanded to other ARL programs. As an example, SEM might have a profound impact on the programs involving quantum chemical modeling by combining modeling efforts with the problem of identifying experimental programs that will serve to validate and instill confidence in the models.

Also newly presented was the development of the Novel Energetic Research Facility (NERF), which led to the development of DEMN, an explosive fill. This effort demonstrates a continued paradigm shift from looking for one magic explosive material to using calculations and experience to suggest a mixture of materials providing tailor-made performance.

During the 2006 review, the panel learned of a new program—Soft Tissue Physics and Applications—and offered numerous suggestions for its improvement. During the 2008 review, it was obvious that WMRD had taken those suggestions to heart, and the group is to be commended for its successful effort in refocusing the program, which addresses a national defense priority and now seems to be going in the right direction. The understanding of munitions-induced trauma is of high importance in the design of armor, in the design of armaments (e.g., to reduce the risk of collateral damage to noncombatants), in the design and delivery of effective treatment of the wounded, and in the training of medical personnel. Blunt trauma and traumatic brain injury (TBI) have very high profiles with the public and the Congress; hence, WMRD’s efforts in modeling blast loading are timely.

ACCOMPLISHMENTS AND ADVANCEMENTS

Materials

A very important element of the materials effort in WMRD is the formation of several Materials Centers of Excellence (MCoEs) in which the scientific input of academia is melded with the technology-driven, warfighter-focused programs at ARL. Currently, five MCoEs are being funded—at the Johns Hopkins University, Rutgers University, the University of Delaware, Virginia Polytechnic Institute and State University (Virginia Tech), and Drexel University. Some of their contributions include the following: (1) work on developing phase diagrams for glassy grain boundary phases in grain boundary engineered boron carbide—necessary for improving the consistency of armor protection of this very lightweight ceramic armor; (2) development of magnesium (Mg) as a lightweight metallic armor; (3) nanocrystalline tungsten (W) to replace depleted uranium (DU); and (4) nanocrystalline aluminum having the strength of steel but one-third the density. In addition to their scientific input, the MCoEs have been the source of a number of summer postdoctoral researchers, some of whom have stayed on as staff members.

Metals

The Microscale Compressive Properties of Metallic Glasses project, undertaken in collaboration with the Johns Hopkins University MCoE, explores new microcompression techniques as a method of assessing the properties of metallic glasses. The goal is to measure physical properties of microconstituents to compare with bulk measurements and to inform the models of metallic glasses and composites in the future. This tie to modeling work was not highlighted by WMRD, but it seems to be the only practical use for the results of this work. Extreme care needs to be taken so that experimental variations (notably alignment) do not dominate the observed results. WMRD is encouraged to leverage these measurements with its multiscale modeling interests, because only through linking the micromechanics to larger length scales can it be hoped that the research described will provide new engineering tools of relevance to Army needs. As this technique continues to be developed and tied to single-crystal and multiscale



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