Best mat'l for relay core?

[eromlignod]

Hi guys:

I'm wanting to wind a small coil for use as an electromagnet, like you
might find in a relay. What core material should I use that will give
me the maximum pull without permanently magnetizing? What do they use
in inexpensive relays?

Thanks for any responses.

Don

 

[Jon]

Silicon steel, such as used in power transformers will work. Most
magnetics companies won't sell small quantities. If this is a
one-of-a-kind project, try taking an old transformer apart.

 

[Don A. Gilmore]

"Jon" <jon.lark@l-3com.com> wrote in message
news:1121807782.848654.173900@g47g2000cwa.googlegroups.com...

Silicon steel, such as used in power transformers will work. Most
magnetics companies won't sell small quantities. If this is a
one-of-a-kind project, try taking an old transformer apart.

If I just used plain, low-carbon steel, what caveats would there be?

Don

 

[John Popelish]

Don A. Gilmore wrote:

"Jon" <jon.lark@l-3com.com> wrote in message
news:1121807782.848654.173900@g47g2000cwa.googlegroups.com...

Silicon steel, such as used in power transformers will work. Most
magnetics companies won't sell small quantities. If this is a
one-of-a-kind project, try taking an old transformer apart.



If I just used plain, low-carbon steel, what caveats would there be?

In low carbon steel, I think the grain boundaries have a lot to do
with magnetic remnance. So, if you build some core structure, you
might want to heat it red hot and let it cool as slowly as possible by
wrapping it in a fiberglass blanket or something similar, to let the
grains grow a bit and get a completely softened chunk with no work
hardening.

Then put the windings in it.