Alternating current electrophoretic deposition and infiltration of nanomaterials in aqueous suspension

3^rd International Conference on Smart Materials & Structures

March 20-22, 2017 Orlando, USA

Kati Raju, Wahid Muhamad and Yoon Dang-Hyok

Yeungnam University, South Korea

Posters & Accepted Abstracts: J Material Sci Eng

Abstract :

Electrophoretic deposition (EPD) is attracting many researchers nowadays because of its many advantages, such as simple deposition apparatus, fast growth rate and the ease of deposition with a controlled thickness. Recently, eco-friendly alternating current electrophoretic deposition (AC-EPD) using an aqueous suspension is emerging as a successful processing technique for the deposition of a range of particles, which was proven to minimize the evolution of gas bubbles. In the present work, the asymmetric AC-EPD of various nanoparticles, such as Si, C, �²-SiC, TiO2, Al2O3, BaTiO3 and ZrB2 by aqueous colloidal processing were examined. The rheological behavior of nanoparticles as a function of pH was studied using zeta potential, viscosity and conductivity measurements. By adding a suitable aqueous dispersant and binder at optimum pH, a well-dispersed suspension containing nanoparticles was prepared in deionized water. A square-shaped asymmetric waveform with an asymmetry factor of 4 was considered for AC-EPD. Homogeneous thin and thick films over a large area were deposited successfully by AC-EPD. The microstructure of the deposited green films was observed by transmission and scanning electron microscopy. AC-EPD revealed uniform and crack-free films when compared to the non-uniform film morphology prepared under a direct current (DC). The effects of the AC voltage, frequency and time on the deposit yield were also investigated. In a following step, AC-EPD combined with the application of ultrasonic pulses was used effectively to infiltrate the SiC and ZrB2 nanoparticles with suitable sintering additives into the fine voids of SiC/C fabrics to fabricate tube and square-shaped fiber-reinforced composites for high temperature applications.

Biography :

Email: raju@ynu.ac.kr