The BaTiO_3-ceramics doped with Ho_2O_3 ranging from 0.01 to 1.0 wt%, regarding their microstructural and dielectric characteristics, were investigated in this paper. Doped BaTiO_3 were prepared using conventional method of solid state sintering at 1320°C for four hours. As BaTiO_3 doped ceramics concerns, SEM analysis has shown that in samples doped with a rare-earth ions low level, the grain size is ranged from 20-40μm, while with the higher dopant concentration the abnormal grain growth is inhibited and the grain size is ranged between 2-10 μm. Dielectric measurements were carried out as a function of temperature up tol80°C . The low doped samples sintered at 1320°C , display the high value of dielectric permittivity, at room temperature 2300°C for 0.01Ho/BaTiO_3. A nearly flat permittivity-response was obtained in specimens with higher (1.0 wt%) additive content. The Curie temperature of doped samples is ranged from 124 to 129°C . The Curie constant for all series of samples decreases with increase of dopant concentration and the lowest values were measured from samples doped with 0.01 wt% of aditive. Some parameters as Curie constant (C), Curie temperature (Tc) and a critical exponent of nonlinearity (f) are calculated by using a Curie-Weiss low. New aspect here is fractal correction, introduced as slight variation of temperature T entered from outside, due to three fractal factors α_s,α_p and α_M being responsible for complex geometry of both morphologic and dynamic nature. This correction, naturally has impact on the Curie-Weiss low, which is stressed in this paper.
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