Magnetic fluid - a unique man-made miracle, the brainchild of technical progress and scientific thought of the twentieth century.Unlike the overwhelming majority of the inventions of human genius, such a liquid substance, with strong magnetic properties, there is no parallel in nature.With the rapid development of technology, a characteristic of our time, substances with such unusual properties is more applications.
Magnetic fluid is a fine suspension, in other words, a colloidal solution of ferromagnetic material in a conventional liquid medium which may also serve as ordinary water, and hydrocarbons, and silicon or organofluorine substances.There were such unusual substance for a long time.Even in the mid-sixties, they were synthesized in the United States and the Soviet Union almost simultaneously.
While magnetic fluids used in various space programs, which have been intensively conducted two superpowers.Over a wide range of the scientific community these unusual substances have become available recently.Now the magnetic fluid has been studied extensively by the majority of developed countries with high scientific potential: Japan, France, Germany, Great Britain and others.
These amazing substance unique to its unbeatable combination of high fluidity with exceptional magnetic properties that tens of thousands of orders of magnitude higher than that of any of the known fluids.The secret of this phenomenal magnetization of ferromagnetic materials is dispersed to a size not exceeding ten nanometers, and their subsequent introduction into an ordinary liquid medium.
Thus, a substance with excellent fluidity is initially saturated unimaginable number of powerful permanent magnets miniature spherical shape.Each nanoparticle is covered with protective and repellent film that prevents them from sticking together.The thermal motion of the magnets distributes throughout the volume of the substance, therefore avoiding sedimentation of particles to the bottom.As a result, the magnetic fluid is able to maintain its unique quality and performance for many years.
Each microscopic magnet chaotically circulates in the liquid under the influence of heat.An external magnetic field in a certain way to orient the magnetic moments of the microparticles, which causes changes in the optical, rheological and magnetic properties of the colloidal solution.Consequently, a high level of sensitivity to an external source the suspension of the magnetic field makes it possible to regulate their behavior.Thus, the control itself becomes magnetic fluid, the application of which it is possible for a wide range of applications.
ferromagnetic suspension already used in the manufacture of hard disk drives, where they are applied to the rotating shaft to prevent foreign matter from the outside.Such suspensions are also used in the manufacture of high-frequency speakers in the aerospace and defense industry, optics and medicine, electronics and instrument-making industry.
