Effects of Manganese Addition on Phase Formation, Microstructure and Electrical Properties of Barium Titanate Ceramics

摘要

In this study, the influence of Mn addition on phase formation, microstructure and electrical properties of Ba(Ti_(1-x)Mn_x)O_3 where x = 0.01 to 0.2 was investigated. The XRD patterns showed that the crystal structure of Ba(Ti_(1-x)Mn_x)O_3 at room temperature changed from tetragonal to hexagonal as Mn concentration increased, which also caused the room temperature dielectric constant decrease from 1143 to 47. The microstructure of Ba(Ti_(1-x)Mn_x)O_3 ceramics at low concentration revealed a bimodal microstructure. As the x value increased, the well grown grains decreased with the extent of fine-grained increased. Ferroelectric hysteresis (P-E) loop was not clearly observed as Mn concentration increased because of the formation of paraelectric hexagonal phase.