Effects of Nb-doping and Segregation on the Grain Boundary Plane Distribution in TiO2
نویسنده
چکیده
Orientation imaging microscopy has been used to investigate the effects of Nb doping on the grain boundary plane distributions in TiO2 (rutile). By comparing the grain boundary plane distribution of the undoped material with theoretical estimates of grain boundary energy anisotropy of pure rutile, it is possible to show that the frequency of grain boundary planes is inversely correlated with grain boundary energy. In the case of Nb-doped material, this inverse correlation can also be demonstrated by a comparison of grain boundary plane frequency with measurements of surface energy anisotropy. In addition, by comparing the grain boundary plane distribution of doped and undoped materials with previous measurements of Nb grain boundary segregation in TiO2, as a function of grain boundary plane orientation, it is possible to explain the changes in grain boundary plane distribution which result from doping.
منابع مشابه
Correlation Between Grain-Boundary Segregation and Grain-Boundary Plane Orientation in Nb-Doped TiO2
Grain-boundary (GB) segregation has been measured in Nbdoped TiO2 (rutile) by Auger electron spectroscopy analyses of the two surfaces exposed by inter-granular fracture. In addition, the orientations of the exposed GB planes on both sides of the fracture surface have been determined. A strong anisotropy of GB composition is found. Measurements on 166 individual GB fracture surfaces show that b...
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