Developments in Ceramic Materials Research

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T. T. Basiev, V. A. Demidenko, K. V. Dykel’skii et al.
Figure 19. Characteristic microphotograph of precursor for the Gd 2O 2S: Nd 3+ and La 2O 2S: Nd 3+
ceramics.
The microstructure of the ceramics is studied using optical and electron microscopes.
Characteristic microphotographs of the ceramic samples are presented in Figure 20. For the
Gd2O2S based samples the most typical is the elongated grains shape (Figure 20a, b), as for
the La2O2S ceramics it is isometric (Figure 20c). For the Gd2O2S based ceramics, a clear-cut
correlation between the grain shape and the Nd 3+ impurity concentration is observed.
Whereas for 0.1 wt.% concentration of Nd 3+ the microstructure of ceramics consists of the
mixed shape grains (Figure 20a), a five-fold increase of the impurity concentration makes the
long bar shape the dominant (Figure 20b).
Figure 20 (Continued).
a