Effect of sintering temperature on the properties of modified mechanical alloyed CaCu3Ti4O12

This paper presents the effects of calcination time and sintering temperature on the properties of CaCu₃Ti₄O₁₂. Electroceramic material of CaCu₃Ti₄O₁₂ was prepared using a modified mechanical alloying technique that covers several processes, which are preparation of raw material, mixing and ball milling for 5 hours, calcination, pellet forming and, sintering. The objective of this modified technique is to enable the calcination and sintering processes to be carried out at a shorter time and lower temperature. The x-ray diffraction (XRD) analysis result shows that a single-phase of CaCu₃Ti₄O₁₂ was completely formed by calcination at 750degC for 12 hours. Meanwhile, the grain size of a sample sintered at 1050degC for 24 hours is extremely large, in the range of 20-50 mum obtained from field emission scanning electron microscopy (FESEM) images. The dielectric constant value of 14,635 was obtained at 10 kHz by impedance (LCR) meter in the sintered sample at 1050degC. However, the dielectric constant value of samples sintered at 900 and 950degC is quite low, in the range of 52-119.