Percolation Effect of PZT-BNT Composite System on Sinterability and Dielectrics Behaviour in View of Development of LTCC

Abstract

Ceramic composite of (1−x)Pb(Zr_0.52Ti_0.48)O₃-x Bi_0.5Na_0.5TiO₃ (PZT-BNT, where x = 0, 25, 50, 75, 100 wt%) were developed in LTCC view point. The presence of biphase composition was confirmed by X-ray diffraction (XRD). The microstructural study of compositions by scanning electron microscopy (SEM) reveals mixing of two phases in powder form of composites. Good densification of compacted pellet of bulk ceramics was also confirmed by SEM. Sintering temperature was reduced from 1270°C for PZT-phase to 1000°C for PZT-BNT composite phases. Enhancement of sinterability of composite system was assigned to solid-state bimodal mixed-phase sintering approach. Dielectric permittivity as a function of temperature exhibits diffuse phase transition in composite system. Complex dielectric permittivity with respect to frequency shows a dispersive behaviour due to Maxwell-Wagner effect at low frequency and Debye relaxation at high frequency range. The percolation effect between two ceramics phases on enhancement of sinterability and dielectric behaviour of the composites is intriguing feature of the work.

Keywords:

• PZT-BNT composite; LTCC sintering; percolation effect

Funding

One of the authors, Shraddha Joshi, wants to acknowledge UGC, New Delhi, India for providing financial support through UGC-BSR fellowship. Shahin Sayyed wants to acknowledge UGC, New Delhi for MANF fellowship.