Subsolidus phase relationship in the Y2O3-Mn3O4-CoOx system in air

Lead zirconate titanate, Pb(Zr,Ti)O3 (PZT), ceramics are ferroelectrics formed as solid solutions between ferroelectric PbTiO3 and ant iferroelectric PbZrO3. The subsolidus phase diagram is shown in figure 1. PZT transforms between the Ti-rich tetragonal (T) and the Zr-rich rhombohedral (R) phases at a composition which is nearly independent of temperature. This phenomenon is called morphotropism, and the boundary between the two phases is known as the morphotropic phase boundary (MPB). The excellent piezoelectric and dielectric properties occurring at this composition are believed to.be due to the coexistence of T and R phases, which results in easy poling (i.e. orientation of individual grain polarizations in the direction of an applied electric field). However, there is little direct proof of the coexistence of the two phases at the MPB, possibly because of the difficulty of distinguishing between them. In this investigation a CBD method was found which would successfully differentiate between the phases, and this was applied to confirm the coexistence of the two phases.

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Core‒Rim Structures and Hierarchical Phase Relationship for Hot-Pressed ZrB 2‒SiC‒MC (M=Nb, Hf, Ta, W) Ceramics

SSRN Electronic Journal ◽

10.2139/ssrn.3358890 ◽

2019 ◽

Author(s):

Dong-Li Hu ◽

Hui Gu ◽

Ji Zou ◽

Qiang Zheng ◽

Guo-Jun Zhang

Keyword(s):

Phase Relationship

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BEAUTY AND COMPLEXITY OF LABRADORITE FELDSPARS: THEIR INCOMMENSURATELY MODULATED STRUCTURES AND SUBSOLIDUS PHASE RELATIONS

10.1130/abs/2019am-339623 ◽

2019 ◽

Author(s):

Huifang Xu ◽

◽

Shiyun Jin ◽

Seungyeol Lee

Keyword(s):

Phase Relations ◽

Subsolidus Phase ◽

Modulated Structures

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Revisiting the Bøggild Intergrowth in Iridescent Labradorite Feldspars: Ordering, Kinetics, and Phase Equilibria

Minerals ◽

10.3390/min11070727 ◽

2021 ◽

Vol 11 (7) ◽

pp. 727

Author(s):

Shiyun Jin ◽

Huifang Xu ◽

Seungyeol Lee

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Atom Probe ◽

Phase Region ◽

Two Phase ◽

Subsolidus Phase ◽

Plagioclase Feldspar ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission

The enigmatic Bøggild intergrowth in iridescent labradorite crystals was revisited in light of recent work on the incommensurately modulated structures in the intermediated plagioclase. Five igneous samples and one metamorphic labradorite sample with various compositions and lamellar thicknesses were studied in this paper. The lamellar textures were characterized with conventional transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). The compositions of individual lamellae were analyzed with high-resolution energy-dispersive X-ray spectroscopy (EDS) mapping and atom probe tomography (APT). The average structure states of the studied samples were also compared with single-crystal X-ray diffraction data (SC-XRD). The Na-rich lamellae have a composition of An44–48, and the Ca-rich lamellae range from An56 to An63. Significant differences between the lamellar compositions of different samples were observed. The compositions of the Bøggild intergrowth do not only depend on the bulk compositions, but also on the thermal history of the host rock. The implications on the subsolidus phase relationships of the plagioclase feldspar solid solution are discussed. The results cannot be explained by a regular symmetrical solvus such as the Bøggild gap, but they support an inclined two-phase region that closes at low temperature.

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