Abstract This paper reviews the synthesis of BaTiO3-based ceramic and composites through the cold sintering process. Cold sintering is a densification process that works with a low-temperature mechanism known as pressure solution creep. This provides several opportunities to fabricate BaTiO3into new composite structures that could provide important advanced dielectric properties. Here we revisit the challenges of densifying a material such as BaTiO3that has incongruent dissolution. We consider the issues of surface chemistry, selection of transient flux, core–shell designs in BaTiO3, co-sintering with polymers in the grain boundaries and the technical challenges associated with incorporating all these ideas into tape casting steps for future fabrication of multilayer device structures.
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Impact of PTFE particle size in designing BaTiO 3 dielectric composites under the cold sintering process
Abstract The Cold Sintering Process (CSP) can provide opportunities to fabricate high-performance BaTiO3dielectric composites with polymer materials that are typically difficult to impossible to co-process under a conventional sintering process. Therefore, we investigated the preparation process of BaTiO3sintered body by CSP and integrated a well-dispersed intergranular polymer phase. In this study, we focused on preparing BaTiO3and Polytetrafluoroethylene (PTFE) composites. We considered the importance of the particle size of the PTFE phase, and correlated the impact on the composite dielectric properties. Through fitting a general-mixing-law to the dielectric properties as a function of volume fraction, we could deduce more homogeneous composites obtained in using the 200 nm PTFE powders. In addition, the temperature dependent dielectric properties and field dependent conductivity of the composites was investigated. It was found that with the good dispersion of the PTFE can suppress the leakage current density in the dielectric composites.
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- Award ID(s):
- 2134643
- PAR ID:
- 10502865
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- Japanese Journal of Applied Physics
- Volume:
- 62
- Issue:
- 7
- ISSN:
- 0021-4922
- Page Range / eLocation ID:
- 071003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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