Electric field‐assisted solid‐state reaction of BaCO <sub>3</sub> ‐TiO <sub>2</sub> system
Yan Zhu, Baisheng Ma, Kewei Wang, Zhenzhong Sun, Ke Ren, Yiguang Wang
Abstract
Abstract We report phase transition process during the solid‐state reaction of BaCO 3 ‐TiO 2 system under the assistance of electric field. Experiments were conducted at a constant heating rate with preset field strength and current limit. Solid‐state reaction was completed upon reactive flash sintering taking place at ~1002℃ under 200 V/cm. Hexagonal BaTiO 3 phase, which rarely occurs at such temperatures, was obtained after flash sintering at a current density of 23.5 mA/mm 2 . It is speculated that oxygen deficiency during flash sintering triggered cubic‐to‐hexagonal transition of BaTiO 3 . Furthermore, X‐ray diffraction results show that solid‐state reaction takes place prior to flash sintering. Electric field could accelerate the reaction but did not alter the sequence of phase evolution.