Product Briefing Outline: Ferrotec Corporation has
made improvements to the standard ferrofluid magnetic liquids which
provide the core sealing function in Ferrotec's ‘Ferrofluidic' vacuum
rotary feedthroughs. Ferrotec vacuum feedthroughs are used in
semiconductor manufacturing equipment, vacuum chambers, and other clean
and controlled process environments. Ferrotec claims the new liquid
improvements have reduced operating torque, reduced vapor pressure, and
provided better thermal stability in demanding process environments.
Problem: A Ferrofluidic seal uses magnetic
liquid and a permanent magnet to form a dynamic "o-ring" around a
rotating shaft. This o-ring forms a barrier between the atmosphere and
the process side of vacuum, ultra-clean, or aggressive gas
environments. Depending upon the application where the vacuum rotary
feedthrough is being used, the quality and the attributes of the
ferrofluid used inside the seal can affect the performance
characteristics of the seal.
Solution:
Ferrotec's enhanced ferrofluid is offered in two options, for standard
environments and for reactive gasses. Standard ferrofluid delivers
optimal performance in most vacuum or non-reactive gas applications.
Ferrotec's reactive gas ferrofluid trades higher viscosity and
increased seal torque for improved performance in more demanding
environments, such as ultra-high vacuum (UHV) use, high temperatures,
and applications that expose the seal to aggressive or reactive gasses.
With one-third less viscosity than the previous generation of standard
ferrofluid, the improved standard ferrofluid offers vacuum feedthrough
users reduced start-up torque, improved thermal stability, and reduced
vapor pressure. For reactive gas applications, the improved reactive
gas fluid offers dramatically increased thermal stability and vapor
pressure has been reduced by an order of magnitude.
Applications: Wide range of sealing applications within process tools, gas systems etc...
Platform:
Ferrotec's new ferrofluids are available in all standard Ferrotec
vacuum rotary feedthroughs. Ferrofluids are a unique class of material.
A ferrofluid is a stable colloidal suspension of sub-domain magnetic
nano particles in a liquid carrier. The particles, which have an
average size of about 100Å (10nm), are coated with a stabilizing
dispersing agent (surfactant) which prevents particle agglomeration
even when a strong magnetic field gradient is applied to the ferrofluid.
Availability: July 2006 onwards.