Eur. Phys. J. E (2005) 17: 63-67
https://doi.org/10.1140/epje/i2004-10108-y

Original Article

An enhanced polarization mechanism for the metal cations modified amorphous TiO₂ based electrorheological materials

State Key Laboratory of Metal Matrix Composites, Shanghai Jiaotong University, 200030, Shanghai, PRC

^* e-mail: oicqing@yahoo.com

Received: 8 May 2004
Accepted: 21 February 2005
Published online: 1 April 2005

Abstract

In the present work, we developed a new kind of electrorheological (ER) materials, metal cations modified amorphous TiO₂ gels. The static yield stress of Sn⁴⁺ modified amorphous TiO₂ gel based ER fluid with a volume fraction Φ = 38% reaches 26.2 kPa at E = 3.5 kV/mm. The result shows that metal cations can significantly enhance the ER activity of amorphous TiO₂ gels. We then proposed a novel ER effect mechanism (metal cations enhanced polarization mechanism) to clarify the experimental results. We believe that it is the metal cations that enhanced the polarization of the polar groups (-OH) which results in the corresponding enhancement of the interfacial polarization.