The Materials Division of the Office of Naval Research (ONR) has funded research on the synthesis and processing of nanostructured materials for nearly a decade. For most of that time, the primary focus has been on chemical routes to synthesis of nanoscale powder, including the spray conversion process that has now been fully commercialized. With the advent of a large number of viable synthesis techniques and considerable progress in commercialization, funding was shifted to the processing of nanoscale powder into bulk structures and coatings. These structures and coatings may be of interest because of the processing advantages of using nanoscale powder (and may or may not be nanostructured in final form), or may exhibit some outstanding property made possible by an ultrafine microstructure, such as hardness or wear resistance. At the current time, research and development efforts are geared toward materials of interest because of their mechanical properties (including thermal barrier coatings), with little (but not zero) work on optical, electronic, or magnetic materials. In addition, all funding is directed toward three-dimensional nanostructured materials (i.e., no fibers or multilayers), a restriction based on fiscal limitations rather than lack of interest. The current annual level of funding is $3 million.
The largest portion of ONR funding in this area goes to thermal spray processing of nanostructured coatings. This is an integrated program encompassing basic and applied research as well as prototype development and technology insertion. Most of the work is being performed by two large consortia, one concentrating on alloys and cermets, the other on ceramics. The work includes process modeling and process diagnostics (leading to real time process control); fundamental studies of wear, toughness, and corrosion; structure property relationships; and product development. Other ONR-funded efforts include processing of bulk non-oxide ceramics (e.g., AlN), fundamental studies of deformation in hard nanostructured composites, and processing of Al- and Ni-based alloys by cryomilling.
A significant research program is being carried out at the Naval Research Laboratory (NRL), partly funded by NRL internal funding and partly by ONR. This effort emphasizes technological and economical aspects of solution chemistry-based techniques for depositing multilayered, nanostructured metallic, ceramic, and composite coatings with enhanced properties. There is an additional emphasis on multifunctional (smart) coatings and on replacement of environmentally unacceptable coating techniques such as chrome plating.
The Materials Division will spend approximately $3 million on nanostructured materials in FY98, a little less in FY99. There is no MURI (multidisciplinary research initiative) component to this ONR program.