Dislocations in Polycrystalline Barium Titanate Fabricated by Spark Plasma Sintering

ABSTRACT

Dislocations offer a promising route for tuning functional properties in ferroelectric materials, yet their controlled introduction into brittle polycrystalline ceramics remains challenging. Here, we introduce high‐density dislocation networks into polycrystalline BaTiO ₃ ceramics via spark plasma sintering (SPS) at 1150°C within minutes under 100–150 MPa. Compared with conventionally sintered reference samples (1350°C, 6 h), the SPS‐processed samples exhibit significantly enhanced permittivity and reduced dielectric loss, along with decreased polarization, increased coercive field, and suppressed strain, which is consistent with dislocation‐mediated domain wall pinning. Moreover, the electrical conductivity substantially decreases with increasing activation energy, which is attributed to the space‐charge regions around dislocation cores impeding charge transport. This work establishes SPS as an energy‐efficient platform for dislocation engineering in ferroelectrics, enabling simultaneous densification and defect introduction, and provides fundamental insights into dislocation‐mediated functional responses in polycrystalline oxides. Our findings open a pathway for designing high‐performance dielectric ceramics through controlled dislocation engineering.