Fundamentals of Ceramic Particle Interactions with AC Electric Fields in Aqueous Media for Applications to Hierarchical Materials
Abstract
This research seeks to develop fundamental knowledge of the mechanisms that underpin the interactions between ceramic particles suspended in aqueous media and external alternating current (AC) electric field. Application of an AC electric field to a media containing particles of electrical properties different than the media causes electric field nonuniformity. The particles in the media experience frequency-dependent polarization, and the interactions of the induced diploes with the nonuniform electric field results in the dielectrophoretic (DEP) forces, which cause particle motion and mutual interactions of particles. The AC dielectrophoresis is an attractive mechanism for particle manipulation in a media and advantageous over other energized fields. However, the application of the AC dielectrophoresis has been primarily limited to manipulation of polymeric particles in non-aqueous media, causing a knowledge barrier for implementation to aqueous ceramic suspensions. The knowledge of interactions between ceramic particles in aqueous media and external AC electric fields will be central to realize the full potential of the AC dielectrophoresis in ceramic processing for particle motion, spatial redistribution, and assembly in the synthesis of novel ceramic materials and structures. The research hypothesis is that for application of an AC electric field to aqueous ceramic suspension initially containing homogeneously distributed particles, the DEP forces will first cause particle motion and enable the formation of particle chains. With the continued application of the field, the chains will grow and with sufficient time start to settle due to the influence of the gravity. The intensity of field-particle interactions and mutual interactions of particles will influence motion, chain formation, and settling of particles. Deciphering the mechanisms of the interactions would be central to achieve controlled manipulation of ceramic particles in aqueous media. The specific research aims are to (i) investigate the role of dielectric permittivity of the ceramic, particle size, ceramic content of aqueous suspension, and AC electric field parameters in the interactions, and (ii) reveal the underlying mechanisms that govern the interactions. The key outcomes will be the knowledge of critical parameters and mechanisms, which can be leveraged to control the level of field-particle interactions and mutual interactions of particles in aqueous ceramic suspensions. Application of AC electric fields to aqueous ceramic suspensions for particle manipulation is an interdisciplinary research problem, connecting materials science and thermal/fluid science. This research problem will be addressed through the integration of experiments and computational modeling. From the integration of experimental and modeling results, a quantitative understanding will be developed of the underlying mechanisms that are responsible for the manipulation of ceramic particles in the aqueous media using AC electric fields. This research will investigate the following model materials in aqueous (deionized water) suspensions: alumina, a weakly dielectric ceramic, and barium titanate, a high permittivity ceramic. The methodologies developed on these model materials and the underlying fundamental knowledge of the electric field-particle interactions will be readily applicable to other oxide and non-oxide ceramics. This transformative research has the potential to provide a new paradigm to advance ceramic processing in the creation of revolutionary materials and structures. It is emphasized here that this proposal is not developing ceramic structures but focusing on fundamental knowledge generation on the interactions between ceramic particles in aqueous media and external AC electric field to affect particle motion in the aqueous media. This knowledge will have direct implications for the development of hierarchical ceramics and composites for the US Army.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 28, 2023
- Source ID
- W911NF2310185
Entities
People
- Dipankar Ghosh
Organizations
- Army Contracting Command
- Old Dominion University
- United States Army