| Abstract |
| Morphology and microstructure of Sr aluminate:Eu/Dy phosphor storage particles fabricated by a plasma spray method and a usual sintering method have been investigated by means of X-ray diffraction, Xray energy dispersive spectroscopy, and scanning and transmission electron microscopy. It has been confirmed that the phases and the morphologies of Sr aluminate:Eu/Dy phosphor storage particles were quite different in accordance with fabrication methods of phosphor storage particles. The morphology of phosphor storage particles was spherical in the plasma spray method, but that of phosphor storage particles was multi-plane type in the sintering method. Large amounts of Sr(Dy·EU)2O4 particles, which formed probably during sintering at high temperature and reduce the properties of phosphor storage material owing to the decrease of Eu/Dy solubility in the matrix phase, were distributed within phosphor storage particles prepared by the sintering method. On the contrary, only a few Sr(Dy·EU)2O4 particles were observed within phosphor storage particles prepared by the plasma spray method, leading to the increase of the properties of phosphor storage material. This is probably due to the fact that the nucleation of Sr(Dy·Eu)2O4 particles are suppressed by the rapid quenching from high temperature into room temperature. Crystal defects such as twins were observed within α-SrAl2O4 phosphor storage particles, resulting in the change of crystal fields. |
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| Key Words |
| Strontium aluminate, Storage phosphor material, Plasma spray method, Morphology; Microstructure |
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