Consolidation Methods for Nanoparticulate Materials

Nanoparticulates of may materials have been fabricated and characterized for over 10 years. Synthesis of ceramics, metals, intermetallics, and ceramic-metal composites can be found readily in the literature. Yet, most development effors to date have emphasized the formation of particulates and their characterization. Very few of the researchers have addressed the formidable problems of handling kilograms of such materials, forming of intermediate shapes (preform), or proceeding directly to final consolidation from the original nanomaterial. It is obvious that if engineering applications for nanomaterials are to be found, cost effective technologies to form dense, near net shape bodies must be developed. This Phase I effort proposes an evaluation of three promising but emerging consolidation techniques; plasma activated sintering, hot isostatic forging and electro discharge compaction. We will explore these techniques for their utility in consolidating nanoparticulates of interest to the Army as potential structural materials. We will perform nanoparticulate synthesis using the pulsed reactive electrode technique developed at MMI for tungsten, tungsten composites, and intermetallic aluminide or a silicide as well as commercially available nanomaterials - a ceramic material and another tungsten material synthesized using other methods such as sputtering or spray forming/CVD. We will fabricate specimens of the avove materials which can be characterized for density, microstrucutre and hardness. Finally, we will evaluate the state of development of each process and estimate its potential for scale up to fabricate commercially viable, cost effective components of interest to the Army. Phase II will then attempt to fabricate prototypes of such components and characterize them for potential use in Army systems.