Smart Materials

There are a large number of smart materials presently in common usage.
These include:
Smart fluids e.g. ferrofluids and electro- and magnetorheological fluids and their respective elastomeric versions.

The ferroelectric family of materials includes piezoelectric, electrostrictive, photostrictive etc.
In addition, magnetostrictive and new magnetic materials are of considerable interest.
Firmerly activated smart materials include shape memory alloys and polymers.

General forms of small particle migration include:


Electrophoresis

In addition to the more common biochemical applications, electrophoresis is a common phenomena experienced in electrorheological devices.

Magnetophoresis

The magnetic counterpart of electrophoresis is magnetophoresis. This is a technique often used to seperate magnetic particles of different size in, for example, magnetorheological and ferrofluids.


Thermophoresis

In a thermal gradient, particles tend to move from hotter to colder regions. Where isotropic mixtures are concerned, larger partciles move from hot to cold and the smaller particles from cold to hot regions.

This principle (also called thermodiffusion or Soret effect) is used for refining materials.

Photophoresis

Photophoresis is the phenomenon that intense light can induce motion in particles suspended in a gas. This is effectively thermophoresis on individual particles.

Acustophoresis

A technique used for particle analysis (often utilised by the paper industry).