Re: Where to scavenge mu-metal?

On 4/11/07 5:07 PM, in article 131qqchsaib3pe8@xxxxxxxxxxxxxxxxxx, "Chris
Jones" <lugnut808@xxxxxxxxxxxxxxxx> wrote:

I have vague memories of hearing that if you bend it (or straighten it) then
it loses its special properties and needs to be re-annealed in some fancy
vacuum furnace thing or something like that. If you found a weird-shaped
piece of this stuff inside an old oscilloscope then I I'm not sure that you
could use it unless you needed it in exactly the shape that you found it
in.
There is good reason for this. Bending, especially repeated bending could
harden pure iron by introducing dislocations. The dislocations pin the
magnetic domains. This is the background to the distinction between
literally hard and soft magnets. Proper annealing would anneal out the
dislocations.

Bill
-- Fermez le Bush--about two years to go.


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