LAUSR

Abstract Effects of trace BaCO 3 addition were investigated on microstructure and electrical properties of La-doped BaTiO 3 ceramics prepared via reduction-reoxidation method. The addition of BaCO 3 could effectively facilitate the densification and grain growth of ceramics. SEM images suggested that numerous pores presented in ceramics due to the decomposition of BaCO 3 to expel generated CO 2 gas. The presence of pores promoted reoxidation of the reduced ceramics. As a result, lowering room-temperature (RT) resistivity and improving PTCR jump were simultaneously achieved as suitable amount of BaCO 3 was added. An optimal addition of 0.3 mol% BaCO 3 led to a low RT resistivity of about 28 Ω cm and a PTCR jump up to 10 3.7 after ceramics were fired at 1100 °C in high-purity N 2 and reoxidized at 800 °C in air.