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The growth of abnormal grains of PMN-35PT containing ∑3 twin boundaries was compared with that of untwinned abnormal grains of PMN-35PT. It was thought that the twinned abnormal grains might have a growth advantage because of the presence of reentrant edges. The aforementioned types of grains were embedded in a PMN-35PT polycrystalline matrix with 3 vol% excess PbO, and grown by annealing in an oxygen atmosphere at 1150°C for varying times. It was found that abnormal grains containing ∑3 boundaries showed a comparable degree of growth to that of the untwinned grains. Furthermore, for the twinned seed crystals, the extent of growth was independent of whether there was any initial entrapped porosity within the abnormal grain. [ABSTRACT FROM AUTHOR]

The kinetics of {001}-oriented Pb(Mg[sub ⅓]Nb[sub 2/3])O[sub 3]-35 mol% PbTiO[sub 3] (PMN-35PT) single crystals grown by seeded polycrystal conversion were systematically quantified as a function of excess PbO liquid phase. The coarsening behavior of the corresponding matrix grains was similarly quantified. Singlecrystal seed plates were embedded in a matrix of PMN-35PT with varying amounts of liquid phase (PbO) content in the range of 0 to 5 vol% and annealed at 1150°C for 0-10 h. Apparent maxima in the growth rates were observed at a PbO content of ∼3 vol% for both the single crystal and matrix grains. In both cases, the growth data were found to most closely follow cubic growth kinetics. Implications regarding the effect of PbO volume fraction on the matrix and singlecrystal growth mechanisms are discussed. [ABSTRACT FROM AUTHOR]

Highlights • Aerosol deposition is used to grow barium hexaferrite films. • A 4 kOe magnetic field was placed during deposition to magnetically orient the films. • Films are found to be oriented out-of-plane. • Sintering the films further improved the magnetic properties. • March-Dollase factor finds 29% grain alignment. Abstract We have deposited polycrystalline films of barium hexaferrite utilizing aerosol deposition at room temperature. Magnetic orientation was achieved by using a 4 kOe permanent magnet mounted in close proximity to the substrate during deposition. We find that these films show crystallographic orientation and magnetic anisotropy out of plane corresponding to the {0 0 2 l } diffraction planes. To further explore the film properties we performed sintering treatments up to 1000 °C and found that the magnetic properties are further improved. For these films the magnetic saturation is 3683 G with a squareness value of 0.82. The magnetic and crystallographic texturing indicate 29% grain orientation with a coercivity of 4.6 kOe. These values indicate that the films are of good quality for potential integration into microwave systems that require high values of saturation magnetization, squareness, and coercivity with a good degree of self-bias. [ABSTRACT FROM AUTHOR]