Magnetic fluid is an unusual fluid in that it is attracted to a magnet. In the 1960s, NASA developed the magnetic fluid as part of its space programs. Magnetic fluid has three ingredients: ferromagnetic particles such as magnetite and composite ferrite, surfactant, and a base liquid such as water or oil. The surfactant coats the 10 nm-dia ferromagnetic particles to avoid coagulation and keep them stably dispersed in the base liquid, forming a ferromagnetic fluid. Its dispersibility also remains stable in high magnetic fields.
This photo shows a phenomenon called 'spiking' that occurs when magnetic fluid is placed in a container and a magnet is brought under the container. Magnetic force acting on the surface of the magnetic fluid produces 'spikes', that look like large nails sticking out of the surface.
Vapor pressure - temperature characteristics Vi scosity - temperature characteristics
Magnetic fluid/ferrofluid feedthrougs
Fluid Sealing feed-throughs have been widely used in sealing various vacuum equipments, like, vacuum furnace, sinter furnace, brazier, hardening furnace, heat-treating furnace, monocrystalline silicon furnace, vacuum pump, film-coating machine, chemical gas deposit equipment, ion beam etching machine, molecular pump, ultrahigh-speed centrifugal machine and so on.
Some feedthroughs produced:
Vacuum Degree :
Leakage Rate :
Pressure Resistance :
Temperature Range :
Sealing Material :
Shell Material :
Non-Magnetic Permeability Stainless Steel
Spindle(Bush) Material :
Magnetic Permeability Stainless Steel
Stainless steel or Aluminum
Water Cooling :
Without / with
An example of an ultra-high vacuum system with the magnetic rotary seal
We can design special magntice fluid sealing feedthroughs as per customers' equipment requirements.