International Conference on Natural Science and Engineering (ICNASE’16) March 19-20, 2016, Kilis 3256 | Page www.icnase16.com ICNASE’16 Ultrasonication Time and Cycle Effects on Thermal Properties of SrCO 3 , BaCO 3 , TiO 2 and ZrO 2 Powders Hatice Zehra Akbas  Department of Physics, Faculty of Science and Letters, Mustafa Kemal University, Hatay Zeki Aydin Department of Physics, Faculty of Science and Letters, Mustafa Kemal University, Hatay Ismail Hakkı Karahan Department of Chemistry, Faculty of Science and Letters, Mustafa Kemal University, Hatay Tuncay Dilsizoglu Department of Physics, Faculty of Science and Letters, Mustafa Kemal University, Hatay Selvin Turgut MARGEM, Mustafa Kemal University, Hatay ABSTRACT The SrCO3, BaCO3, TiO2 and ZrO2 powders can be activated by high intensity ultrasonic waves (ultrasonication). Both the ultrasonication time and cycle are the important parameters in the activation process. The effect of the ultrasonication time on thermal properties of SrCO3, BaCO3, TiO2 and ZrO2 powders have been investigated in this study. The powders activated for different ultrasonication times (30 minutes and 3 hours) and cycle (cycle=1 is continues mode and cycle=0.5 is 50% discontinues mode and %50 continues mode). Termogravimetrik (TGA) and differential scanning calorimeter (DSC) analysis used to investigate of the thermal properties of the powders. The thermal properties of the powders influenced ultrasonication time and cycle, while the phase of powders was maintained. Keywords: ultrasonication, time effect, cycle effect, thermal properties. 1 INTRODUCTION The powders of metal oxide and carbonates have been used very wide industrial application from engineering to health. BaTiO3, SrTiO3, BaSrTiO3, ZrO2 ceramics are lead-free ceramics which ones are very important for many electronic applications [1–5]. The commercial powders have about 1 μm particle size. The decreasing grain size of the powders is required to achieve dense ceramics with exceptional properties [6–10]. Therefore, the methods of decreasing BaTiO3 powders size have been attracting because of their application in fundamental research. For example, if TiO2 powder has about 10 nm particle size or less, it’s colour change from white to black. While the color of the TiO2 changed from white to black, the bandgap changed from 3.3 eV to around 1 eV [11]. The starting powders can be mechanically activated such as a high-energy plenetary mill [12–14], high-energy shaker mill [15], planetary ball mill [16] to activate the surface energy. In these studies, it is  hatice-akbas@windowslive.com (corresponding author)