This Small Business Innovative Research Phase I project describes the synthesis and consolidation of nanocrystalline yttrium iron garnet (YIG). YIG is an important material for many high-technology devices. YIG has been used extensively in the polycrystalline, single crystal, and thin film forms. Its crystal structure is that of the garnet mineral Mn3Al2Si3O12. Si and Mn are substituted by Y and Fe to obtain Y3Fe5O13. YIG has the lowest resonance linewidth ever observed, and this property makes it commercially significant. The presence of pores, nonmagnetic impurities and microstructural inhomogeneities broaden the resonance linewidth and deteriorate the properties. Nanoparticles have high coercive force and high saturation magnetization. They also offer the ability to be consolidated into higher densities than micron sized powders. Materials Modification, Inc. (MMI) proposes to synthesize nanosized powders of YIG and rapidly consolidate them using a Plasma Pressure Consolidation (P2C) technique into fully dense shapes.<br/><br/>YIG is applicable to high frequency microwave applications such as filters, oscillators, multipliers, detectors, resonance isolators and gyrators.