The influence of shaping process on microstructure and properties of BaTiO3-based chip thermistors

BaTiO3-based chip ceramics with a thickness of 0.3 mm were prepared by three different forming techniques: gelcasting, slipcasting and roll-forming. The resistance–temperature and voltage–current characteristics of the obtained chip ceramics were studied. The influence of forming process on microstructures of green sheets and ceramic bodies was also analyzed in detail. The results indicate that gelcast and slipcast ceramics possessing more uniform microstructure exhibit stronger PTC (positive temperature coefficient) effect and higher withstand voltage than roll-formed ones.