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Abstract: Pb(Zr x Ti1−x )O3 thin films with mixed orientations of (111) and (100) were prepared on Pt/Ti/SiO2/Si substrate by sol–gel technique. The compositions of PZT thin films are chosen as x =0.55 and x =0.58. Both of the compositions are in the rhombohedral phase region of the Pb(Zr x Ti1−x )O3 phase diagram, but the former is near the monoclinic phase existence region, and the latter is far from the monoclinic phase existence region. Rhombohedral–monoclinic phase transitions are reported in both of the thin films. The results show that the phase transition is related to the grain orientation. Phase transitions in the films are clearly identified: rhombohedral phase transforms to MB phase in (111)-oriented grains, and rhombohedral phase transforms to MA phase in (100)-oriented grains. The remnant polarization is determined by the content of (111)-oriented grains. It is shown that the remnant polarization is greater in the film with higher content of (111)-oriented grains. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the chosen composition of PZT film falls in rhombohedral phase region and the dependence of lattice distortion on film thickness in sol–gel derived Pb(Zr0.58Ti0.42)O3 thin films was systematically investigated. The results confirm that the Pb(Zr0.58Ti0.42)O3 films have monoclinic phase even though the composition falls in the rhombohedral phase region. The mixed textures of (100) and (111) occur in the PZT films. In the case of mixed textures, a method using ψ-scan XRD to characterize the phase type of Pb(Zr0.58Ti0.42)O3 film is presented. It is found that the phase type of (100)-oriented grains is MA phase, and that of (111)-oriented grains is MB phase. Moreover, the lattice constants of both MA and MB phases are sensitive to the film thickness. The lattice distortion of monoclinic phase becomes smaller as film thickness increases. [ABSTRACT FROM AUTHOR]

The phase-transformation plasticity of shape-memory polycrystals is closely related to the crystallographic texture because the corresponding single-crystal is strongly anisotropic. In this study, the effect of texture on phase-transformation plasticity has been considered in CuZnAl shape-memory sheets. The textures in the dual-phase and parent austenite states were measured and then analyzed by the orientation distribution functions. The texture of the parent austenite is determined as a [1 1 0] fiber texture. Subsequently, from the texture parameters and single-crystal properties, the recoverable phase-transformation strains in the different directions of the rolling plane were estimated by the statistical averaging method, and the corresponding experiments were performed. It was found that the experimental results are in agreement with the calculated results. It is explained that this anisotropy of phase-transformation plasticity is determined by the preferred distribution of the constituent grain orientations. Through the analysis of texture and transformation strain anisotropy, it is possible to reasonably tailor textured shape-memory materials in practical applications. [Copyright &y& Elsevier]

Abstract: Pb(Zr1−x , Ti x )O3 thin films with different Zr/Ti ratios (0.45≤ x ≤0.49) were prepared by a sol–gel method using nitrate zirconium as starting material and 2-methoxyethanol as solvent. The films were deposited on Pt (111)/Ti/SiO2/Si (100) substrates by spin-coating process and annealed at 650°C for 3min by rapid thermal annealing (RTA). X-ray diffraction (XRD) revealed that the films crystallized in perovskite phase and were all (111)-oriented. The effect of Zr/Ti ratios on the phase components and ferroelectric properties of the thin films was investigated. The result suggests that monoclinic phase and tetragonal phase coexists for the films with 0.47≤ x ≤0.49 and there is a pure monoclinic phase for the films with x ≤0.46. The films with x ≤0.46 exhibit higher remnant polarizations compared with the other films, as is explained by more monoclinic phase content and higher (111) orientation degree. [Copyright &y& Elsevier]

Abstract: Highly (100)-oriented polycrystalline Pb(Zr0.52Ti0.48)O3 films with different thicknesses were fabricated on Pt/Ti/SiO2/Si substrate using typical sol–gel method. The study results indicate that, for the PZT film with composition near morphotropic phase boundary, tensile stress benefits the tetragonal-monoclinic phase transition and the phase transition is very sensitive to stress. The difference in the polarization behavior of the films with different thickness is considered as the result of the preferred orientation and the different monoclinic phase contents in the films. [Copyright &y& Elsevier]