Mg kattkılı CCTO seramiklerin dielektrik özelliklerinin ve karakterizasyonunun incelenmesi

In this work, calcium copper titanate, CaCu3Ti4O12 (CCTO) with magnesium oxide, MgO composition of 0 ≤ x ≤ 0,08 were prepared using the solid-state reaction method followed by sintering of CCTO at 1030oC and for 20 and 40 h, sintering processes were employed in order to improve phase structures, morphology and dielectric properties. XRD and SEM have studied the microstructure, structural morphology of CCTO and Mg-doped CCTO. The dielectric properties of CCTO/ Mg-doped ceramics which prepared using CCTO and MgO powders was studied using impedance spectroscopy. The relative dielectric constants of the samples were examined for frequency dependent changes in the range of 100 Hz to 1 MHz. The doping effect of Mg to CCTO was seen to be able to increase the dielectric constant with maximum dielectric constant shown by x = 0.02, R=1044.28 at 100 Hz for 40 h. The lowest dielectric constant at frequency 100 Hz obtained was shown by pure CCTO with a value of 240.47, which is also evident from the SEM micrographs. The SEM micrograph shows the grains with smooth surfaces associated with cubical appearance for 0.02CCTO20, 0.05CCTO20, and 0.06CCTO40, respectively. SEM results show that doping effectively enhanced grain growth or densification, which should increase the dielectric constant. Efficient crystalline phase formation (for x=0.01, 0.02 and 0.06) accompanied by doped lattice constant expansion was confirmed through X-ray diffraction studies. As a result, the presence of a magnesium oxide phase beside the CCTO plays an important role for enhancing the dielectric properties. Keywords: CaCu3Ti4O12 (CCTO), MgTiO3, Dielectric properties, XRD, SEM.