Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

iron cores

iron cores

iron cores

i was wondering how much difference i can expect in magnetism between two magnetic cores. (i know you guys are gonna slam me for just saying magnetism, but i am a simple man and am just talking about how much attraction the magnet will generate) one would be mild steel 1008, the other standard 1018.  also would these have signifigantly less magnetic pull than one of the designer silicon steels?  the cores are .375 dia. by 1 inch long.  wrapped with 28 ga wire top to bottom 6 layers thick. just wondering if the difference is anything i could experience without the help of diagnostics.
 little help?

RE: iron cores

Hello acmetim,

All other things being equal, you would expect slightly more attraction from the mild steel 1008 than the standard 1018.  The reduced carbon content in the 1008 produces a higher saturation magnetism compared to the 1018.  The higher the saturation magnetism, the higher the magnetic output and thus the higher the attraction force.

The difference will be very small, you'd probably not even notice unless you were specifically measuring the effect.

A silicon steel will be stronger than either the 1008 or the 1018, although you have to be sure the silicon steel is heat treated beforehand.

RE: iron cores

Thi biggest difference between the various grades is that with  the low carbon material you will start to see more force at lower current levels.  At full power the force will depend on where you are in terms of stauration levels.  If you have enough amp-turns to saturate the 1018, and no more, then everything will look the same to you.
If you have less field, then easier to magnetize grades will give you more force.
If you have more field, then higher staturation matierlas will give you more.
The other difference is that the 1018 will probably retain more residual magnetization after the coil is turned off.

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection

RE: iron cores

At what DC voltage do you expect to power this at? And so I don't have to do any more guessing than necessary. Do you know how many turns total you have?


RE: iron cores

the dc voltage will be between 7 and 10 volts depending on the application.  the total turns will be 210 +/- 10.
thanks you guys for the tips.

RE: iron cores

At 10 VDC you will be pulling about 6.7 amps for 67 watts. Your on time will be very limited. This provides 1410 ampturns. The steel reaches only about 7500 gauss in the inside center and about 9800 gauss on a very small part of the outside edge or rim. Just about any steel will work without any real advantage including the 400 series stainless.

This all assumes a perfect lay not random wound. Resistance should be 1.493 ohms. Less and you will pull more current and get hotter faster.

For continuous duty you should be less than 1 watt power. And it will still be hot to the touch.

Be careful you don't burn your fingers or start a fire.


Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close