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Highlights: [•] Fractions of Ti(C, N) precipitates were increased during GBE process. [•] Fraction of twins appeared to affect the formation of non-twin type Σ3. [•] The internal oxidation was interrupted by special boundaries. [•] A model has been developed to relate creep behaviour to special boundary. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic properties and high frequency characteristics of obliquely sputtered Co100− x M x (M=V and Nb) films were investigated. All studied films exhibited strong induced in-plane uniaxial magnetic anisotropy. Less content of Nb (x =7) than V (x =16) is sufficient for Co100− x M x films to become fully amorphous which exhibit the maximum magnetic anisotropy filed, reduced coercivity and the increased resistivity. The optimal properties of 4πM s =11.3kG, H k =350Oe and f FMR =5.6GHz are attained for Co93Nb7 film, which are suitable for up to 5GHz applications. [Copyright &y& Elsevier]

The temperature dependence of the crystal structure for Bi1−2.5 x Pr1.5 x Ba x FeO3 (x =0.05, 0.1) polycrystallines is studied by X-ray powder diffraction with Rietveld refinements in the temperature range of 25–800°C. A structural phase transition of Rhombohedral-to-Cubic occurs for Bi0.875Pr0.075Ba0.05FeO3 sample in the temperature of 600–700°C, which may relate to its unstable rhombohedra distorted structure with the space group R3c. The rarely decomposition of these samples indicates that the Pr, Ba co-doped make the BiFeO3 ceramics more stable. The thermal expansion determined by the temperature dependence of the unit-cell lattice parameters and volumes for Bi1−2.5 x Pr1.5 x Ba x FeO3 samples is also investigated, which shows an isotropic and positive behavior. The average thermal expansion coefficient decreases with the increasing x. We argue that the Cubic crystal structure with the high symmetrical of the space group Pm3m may be more stable for Bi0.75Pr0.15Ba0.1FeO3 sample, which may explain the reason why no phase transition occurs and its lower thermal expansion efficiencies. An obvious change in the slope of the linear fitted lines between 300°C and 400°C suggests a possible antiferromagnetic–paramagnetic transition, which occurs around the Néel temperature of the Bi1−2.5 x Pr1.5 x Ba x FeO3 samples. [ABSTRACT FROM AUTHOR]

The phase transition, ferroelectricity, piezoelectricity, and ferromagnetic characteristics of Bi 1− x (Ba 0.75 Ca 0.25 ) x Fe 1− x Ti x O 3 ( x = 0.2–0.4) ceramics have been systematic studied. The rhombohedral R3c and tetragonal P4mm phases are determined for x = 0.2 and x = 0.4, respectively, and the composition of x = 0.3 indicates the rhombohedral and tetragonal diphase structure. The saturated P – E loop with a significantly enhanced remnant polarization ( P r ∼43 μC/cm 2 by dynamic hysteresis mode (DHM); P r ∼24 μC/cm 2 by positive up negative down (PUND) method) is determined in Bi 0.7 (Ba 0.75 Ca 0.25 ) 0.3 Fe 0.7 Ti 0.3 O 3 ceramics at room temperature. The coercive field is greatly suppressed with increasing x . The enhanced remnant magnetization (0.07 emu/g at 300 K) is also achieved in the optimal composition x = 0.3. The room temperature strain–electric field (s–E) curves indicates a large strain ∼0.2% in the composition of x = 0.3. The comprehensive enhancement of ferroelectricity, piezoelectricity, and magnetization in composition of x = 0.3 suggests that introducing phase boundary is a promoting way to put BiFeO 3 ceramics towards applications. [ABSTRACT FROM AUTHOR]