Study On Ni/Graphite/BaTiO₃-based PTC Composites

Ni/graphite/BaTiO3 composites are fabricated by adding Ni and graphite powders into BaTiO3 calcined powder to achieve low room-temperature resistivity and better PTC effect. In this article, the effects of the Ni content, graphite content on the electronic properties and PTC effect of the Ni/graphite/BaTiO3 composites were discussed, and the influences of technology crafts on the composites were analyzed. By analyzing the data of the experiments, the parameters of the processing condition were manipulated. The microstructure model and the potential barrier model were proposed in this article through analyzing the results and detecting the microstructure by means of XRD,SEM,EDS. Effects of the nickel and graphite on the properties of the composites were discussed by employing these two models, the two models explained phenomena observed in the experiments and regularities deduced from experimental data.