Purpose and area of application

The magnetic liquid is a medium with both magnetic properties and good fluidity. A wide choice of liquid bases of the developed magnetic liquids (water, kerosene, synthetic and mineral oils, perfluorochemical ethers, glycerin etc.) can provide a possibility of magnetic management for many technical devices and technological processes.

In our research laboratory were developed:

• magnetic liquids on various liquid bases with fixed properties,
• magnet liquid seals of mobile shafts,
• magnet liquid dampers,
• control methods of hydrodynamics and heat transfer with the help of magnetic fields.

Technical characteristics

There was developed a new original technology of manufacture of the magnetic liquids with the increased stability in a non-uniform magnetic field. Magnetic liquids can have various properties (density, viscosity, magnetization, evaporation, lubricant properties, heat conductivity, electroconductivity etc.).

Main characteristics of magnetic liquids:

• magnetization of saturation - up to 120 kA/m;
• viscosity - from 0,001 up to 1 Pa s;
• density - from 950 up to 1800 kg/m³;
• working temperature is determined by temperature of boiling of the liquid-carrier.

Examples of realization

Hermetic sealing of mobile shafts

There was developed a new original technology of hermetic sealing of mobile shafts of machines (seal between the case and shaft) with the help of the magnetic liquid, which takes place between areas with different pressure. The application of a new way of introduction and deduction of a magnetic liquid between the case and shaft was achieved due to use of the magnetic field. In the proposed technology there are achieved the high degree of tightness, low losses on friction and due to it the significant economy of expensive raw material and power resources. In traditional capsulators the outflow of the fluid medium is supposed. They differ with the big losses on friction as well. This technology is characterized by simplicity and reliability, opportunity of hermetic sealing of the various mediums used in industrial production.

Main characteristics of seals:

Condensed mediums are vacuum, air, water vapor, biologically active mediums, inert gases;
Linear speed of rotation of a shaft up to 45 km/s;
Working temperature from -50 up to +80 °C;
Pressure difference for air-gas mediums - up to 8*10⁵Pa;
Degree of under-pressure for vacuum systems - up to 10^-7mm merc. c;
Resource of steady work - not less than 5000 hours at ambient temperature up to 50 °C.

Damping devices

There were developed effective magnet liquid damping devices for clearing the free and compelled fluctuations in conditions of impossibility of a support on external objects - at fluctuations of string constructions (aerials), spatial constructions like a plane in conditions of weightlessness (panels of solar batteries, mirror of big telescopes). Dampers were tested on joist and spatial constructions on frequencies from 1 up to 200 Hz with amplitudes of fluctuations 0,1-50 mm. At a parity of a damper weight to varying weight 1:60 values of logarithmic decrements of attenuation 0,5-0,7. The especially high efficiency device have shown at frequencies about 1-2 Hz and at small amplitudes (0,1-0,2 mm).

Variants of cooperation

The laboratory has opportunities of performance of development of magnet liquid devices according to technical requirements of the interested organizations.