Open AccessEffects of mechanical activation on the formation and sintering kinetics of barium strontium titanate ceramics
Author(s) -
Darko Kosanović,
Nebojša Labus,
Jelena Živojinović,
Adriana Peleš Tadić,
Vladimir A. Blagojević,
Vladimir B. Pavlović
Publication year - 2020
Publication title -
science of sintering/science of sintering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.309
H-Index - 25
eISSN - 1820-7413
pISSN - 0350-820X
DOI - 10.2298/sos2004371k
Subject(s) - sintering , materials science , activation energy , ceramic , chemical engineering , kinetics , strontium titanate , strontium , porosity , phase (matter) , barium titanate , mineralogy , composite material , nanotechnology , chemistry , thin film , physics , organic chemistry , quantum mechanics , engineering
The influence of mechanical activation on the formation, sintering kinetics and morphology was investigated in sintered barium strontium titanate (BST) ceramics with different Ba-to-Sr ratios. Initial powders were mechanically activated for 20 and 120 min, leading to mechano-chemical reaction and formation of BaxSr1-xTiO3 phases. Agglomeration was found to represent an important factor in the process of formation of BaxSr1-xTiO3 phases around 800?C and during sintering. It reduces the effectiveness of mechanical activation on formation of BaxSr1-xTiO3 phases beyond the short period (20 min), while in the process of sintering, prolonged mechanical activation (120 min) leads to a significant reduction in sintering temperature and the corresponding value of activation energy. In addition, all three systems show a phase transformation around 1100?C, attributed to the hexagonal-to-cubic phase transition. Morphology of the final sintered ceramics can be correlated primarily with the state of the pre-sintered powder, where mechanically activated powders with smaller particle size produced more compact and less porous final product.