Magnetic fluid is a unique result of technical progress and human genius. Unlike most inventions borrowed from nature, it has no analogues. Due to its unusual properties, magnetic fluid has more and more fields of application: in the military industry, in optics and medicine, in electronics and instrumentation.
What is magnetic fluid
A magnetic fluid, or rather a ferromagnetic fluid, is a liquid that is highly polarized in the presence of a magnetic field. It got its name from the Latin word ferrum, that is, "iron".
Magnetic fluid is nothing more than a highly dispersed suspension. In other words, it is a colloidal system that consists of a carrier liquid and ferromagnetic nanosized particles suspended in it. The carrier liquid can be water, organic solvent, hydrocarbons, organosilicon or organofluorine substances.
The name, however, of these substances does not quite correspond to reality, since such liquids themselves do not exhibit ferromagnetic properties. After the cessation of exposure to a magnetic field, they do not retain residual magnetization. Ferromagnetic fluids are actually only paramagnets or, as they are also called, "superparamagnets" - they are simply very susceptible to a magnetic field.
History of ferromagnetic fluids
Ferromagnetic fluids and similar substances have appeared quite a long time ago. Almost simultaneously, they were created in the 60s of the last century in the USA and the USSR. In those years, they were widely used in various space programs.
These substances are available to other circles of the scientific community not so long ago. Today magnetic fluids are studied in many countries with high scientific potential: Japan, France, Germany and Great Britain.
Application of ferromagnetic fluids
The main and most unique property of all ferromagnetic fluids is their combination of high fluidity with exceptional magnetic properties. For these two indicators, ferromagnetic substances are tens of thousands of times superior to any of the known liquids. It is thanks to these properties that magnetic suspensions have found wide application in various fields.
For example, they are used in electronic devices, using them to create a layer that reliably protects parts from the penetration of foreign particles. And many tweeters use ferrofluids to conduct heat away from the voice coil.
In mechanical engineering, such suspensions are used to reduce friction between individual parts of the assembly.
Magnetic fluids are also used in analytical instruments - thanks to their refractive properties, they have found their niche in optics.
Experiments are also underway on the use of ferromagnetic fluids to remove tumors.