Nature of onset of permanent magnetism in 8620 armature?
Nature of onset of permanent magnetism in 8620 armature?
(OP)
Hello,
I am on a team designing on a solenoid valve, we have had issues with durability of the armature, so are testing a prototype configuration with an 8620 alloy armature instead of the Silicon Iron original armature. The armature is case hardened in either material.
Once concern we have is whether the armature will be develop permanent magnetism over time, after being subjected to the magnetic field. We are trying to drive this phenomena by 1) running durability testing and 2) running over-current tests where we purposely hit the coil with double the normal current for a minute or so, then restore the control current back to normal and look for changes in valve performance. If we had onset of perment magnetism, we would expect longer valve closing times.
My question is, IF we were subject to the onset of permanent magnetism in our armature, would it be something we would see after a short term (mintues), mid term (days), or long term (years) operation in the field?
Thanks in advance,
CSMDakota





RE: Nature of onset of permanent magnetism in 8620 armature?
on hte other hand, this residual will be increased, when the alloy was not originally saturated, and when is now applied double current. The residual could also increase when the valve open and close again and again and the alloy is created consideralbe internal strains, or, is even created additional martensite structure. from this perspective, the "permanent magentism" is long term.
RE: Nature of onset of permanent magnetism in 8620 armature?
Let us know how your tests go.
----------------------------------------
The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
RE: Nature of onset of permanent magnetism in 8620 armature?
And yes it will very quite a bit between lots.
As long as the saturation levels are about the same they should function similarly.
Any change in operation speed would only be at the very start of actuation. It shouldn't have much impact on closure.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
RE: Nature of onset of permanent magnetism in 8620 armature?
RE: Nature of onset of permanent magnetism in 8620 armature?