Ferrofluid is lubricious oil which sticks to the magnets. Though a person may need to have thorough knowledge of chemistry and physics to have complete understanding but the basic fact is that tiny pieces of iron or Ferro are suspended in an oily fluid with a surfactant (a compound which is supposed to lower the surface tension). The ferroluid does not get magnetized without a magnet nearby but it aligns almost instantly when aligned with a magnet. This is what ferrofluid is meant to be. It is necessary to know the history to understand how it works.
In the 1960’s, the NASA scientists developed ferrofluid in an attempt to have moving liquid fuel for a gravity-free outer space setting. In the 1970s, it was developed further to be used as a magnetic liquid leak-free sealing system for rotary gadgets like disk drives of computers which increase the memory capacity and prevented contamination. Later ferrofluid was used in the production process of semiconductor wafers and other vacuum processed high technology products. Today most of the computers feature a ferrofluidic seal.
Ferrofluid has it usage in medicines as well, especially in genetics and molecular diagnostics.
A ferrofluid seal combined with a magnetic circuit makes a hermetic seal against contaminants and vapor. Gas systems like sterilization equipment, X-ray, radiology and other imaging systems widely use this seal technology. It is also used in the vacuum process where rotation is necessary. It creates a liquid o-ring around a rotating shaft with no friction between stationary components and the rotating components. This serves as a seal for rotating mechanisms, blocking out contaminants and atmosphere.
The uses and applications of Ferrofluid have increased over the years from power transformers to enhanced loudspeaker performance to bearings. Sensors and motors have also used ferrofluid where it is used to cool down the wires. It is also used in bearings, engine pistons, and dampers as a sealant. Often times it is also used to test other components like stainless steel, magnetic tapes and turbine blades. Moreover, it is also useful in enhancing the performance in flow meters, vibration, tilt, pressure, and level sensors, and in certain types of switches.
It is necessary to ensure that the material which is exposed to ferrofluid has chemical compatibility. There can be gas exposure like in the laser and semiconductor industries, or liquid sprays like in the aircraft and tool industries. There may also be exposure to lubricant vapors like in the computer industry, adhesives in the loudspeaker industry, or plating and plastic materials. There must be certain temperatures for working of ferrofluid. In winter conditions ferrofluid works between (-20°C) and space environments (-55°C) and there may also be a need to hold up nuclear radiation. Hence it is extremely important to evaluate the exposure cautiously to find out which particular ferrofluid is suitable.
