**3. Characterization of the ER fluid**

### **3.1 Rheological characterization**

Rheological characterization is done to identify the change in viscosity of the ER fluid with respect to the shear rate at various electric fields. Garcia et al. [11]

**137**

*A Review on Electro-Rheological Fluid (ER) and Its Various Technological Applications*

them. High voltage amplifier was used to supply the DC voltage.

and high resistor meter. DC high voltages were used for the test.

have studied the rheological properties of the ER fluid by using ARES rheometer by using parallel plate diameter 50 mm diameter electrode with 1 mm gap between

To study the permittivity and the power factor of the ER fluid the dielectric properties characterization are done. Rejon et al. [12] describes the method of measuring the dielectric properties of the ER fluid. They used guard ring capacitors

The structural changes of the ER field during and before the DC voltage was studied by Rejon et al. [13]. The studied the microscopic structure of the ER fluid by microscope. They studied the microstructural changes of the ER fluid at different

ER fluids have lots of interesting properties which attracts them in various applications fields among the various important properties of the ER fluid lies fast reaction, precise controllability and easy boundary between the electrical and mechanical input output power. Because of these interesting properties of the ER fluid the ER fluid is used in motion control and will be used in various applications fields in the near years to come. ER fluids characteristics in most advanced way is briefly described below as given in latest reports: (a) When external electric field is given ER effect is seen by change in viscosity of the carrier fluid from liquid to solid as the viscosity of the liquid increases and after removal of the electric field solid to liquid viscosity decreases making the liquid less thick like the initial state, (b) the process in which the ER fluid changes its state from liquid to solid upon application of the electric field must be reversible, i.e., it should return back to its original state (liquid state) as soon as the external electric field is removed. Viscosity change must be less step, (c) upon application of the electric field the transition of the liquid state to the solid state must be very fast, i.e., 5–10 s, (d) and liquid to solid transition must be only possible by electric field only and not by any other means. By all these characteristics of the ER fluid the ER fluid can be connected with the modern technological applications. This technology is one newly type of future challenge as its attractive properties are being used broadly, which can bring a big change in industries. The main component of the ER technology is the ER fluid which should bring in the technological applications like dampers of ER fluids which is a best

*DOI: http://dx.doi.org/10.5772/intechopen.90706*

**3.2 Dielectric characterization**

**3.3 Structural characterization**

solution for control of vibrations.

**4. Conclusion**

DC applied voltages from 0.5 to 2.5 KV/mm.

have studied the rheological properties of the ER fluid by using ARES rheometer by using parallel plate diameter 50 mm diameter electrode with 1 mm gap between them. High voltage amplifier was used to supply the DC voltage.
