![]() The deformation rate data for all the crystals obtained from these simulations are analyzed using the method of empirical eigenfunctions and using statistical more » methods. For each of these simulations the model polycrystal is constructed using a different spatial arrangement of the same set of crystals, so as to alter the neighborhood of each crystal. The extent to which interactions between a crystal and its neighbors influence its deformation is examined by conducting a series of simulations. The deformations of model fcc polycrystals are studied using finite element simulations in which each element of the discretization is treated as a single crystal. It provides near-surface mosaic spread and crystallography information with a longitudinal depth resolution of tens of nanometers and is not influenced by grain shapes. The proposed method can be applied to any type of polycrystal and is not limited to HOPG. The study also shows that previous theoretical equations are valid only at small values. The effects of mosaic spread on minimum yield and the half-width at half maximum of angular scans are systematically modeled and compared with previous theoretical equations. is extracted through the best fitting, demonstrating that the method can be used to obtain texture details. The simulated results are compared with experimental results obtained using 1.2 MeV alpha particle. Yield maps are calculated under various values (standard deviations of mosaic spread). The yield map of a single crystal is obtained by a simulation of more » ion trajectories in a potential field described by Moliere screened Coulomb potentials. For highly oriented pyrolytic graphite (HOPG) exhibiting mosaic spread, the method leads to a Gaussian kernel averaging of the map obtained from a single crystal. The final yield map is created after averaging the rotated yields using the texture function as the weight factor. The rotation matrix is determined by the deviation of the crystal axial direction from the original z axis. ![]() We propose a method to convert the channeling Rutherford backscattering spectrum yield map of a single crystal to a polycrystal through a matrix rotation technique. Differences in polarization-versus-electric-field and strain-versus-electric-field behavior between the hot-pressed and annealed materials have been discussed in terms of differences in domain mobility.= , The transition on annealing has been explained in terms of chemical homogenization to a near-morphotropic phase-boundary composition that is intrinsically weak normal-ferroelectric. The as-hot-pressed properties have been explained as being the integrated response of many discrete ferroelectric responses as dictated for each of these regions by the local chemistry. The as-hot-pressed microstructure was chemically heterogeneous, characterized by submicrometer-sized regions of varying magnesium, niobium, and titanium content that likely originated from chemical heterogeneities that were present in the as-prepared PMN-PT powder. Annealing resulted in a transition to weak normal-ferroelectric behavior, a shift in the dielectric maximum temperature from 190☌ to 169☌, and a dramatic increase of to a maximum value of 41 720 for the longer anneal. The as-hot-pressed material exhibited relaxor–ferroelectric-like behavior, with a relatively low dielectric constant maximum measured at 1 kHz of 8160. Dielectric and piezoelectric properties of the as-hot-pressed and annealed samples were measured and correlated with microstructure. Fully dense compacts were formed by hot-pressing the powder at 950☌, and then the compacts were annealed at 1150☌ for 5 and 10 h, respectively. PbO3 (PMN–35PT) powder was prepared using the columbite precursor method.
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