What type of core should I use?

[Wizkid700]

Greetings,

So, what kind of core is best used in an electromagnet? Is it iron?
And is iron the ONLY material commonly used in electromagnets cores?

 

[Skogsgurra]

Yes.
Yes.
Yes. Or steel. Which is iron with carbon and sometimes a few more ingredients in low concentration.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[Wizkid700]

Thanks.

 

[Wizkid700]

Due to the current flow, the whole core will turn into a magnet right?
I'm worried that if there is a magnet in the system. The electromagnet can't push it away, because the magnet is attracted to the iron/steel core...

 

[waross]

As the current and as a result the amp turns increase the electromagnet will become stronger. The strength of the electromagnet must be greater than the permanent magnet or the permanent magnet will be attracted to the electromagnet core.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Wizkid700]

Wouldn't the core become magnetized from the current flowing around it?

 

[waross]

Yes

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Skogsgurra]

I second Bill.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[Wizkid700]

Its confusing to me now...
Lets say we had a Solenoid, it can pull/push a magnet without the trouble of having the magnet attracted to the core.
Now, lets we add an iron/steel core. Its magnetized by the current around it. Why should the magnet be attracted to it? Even if the electromagnet is set to push it away. The magnet should be pushed regardless of the iron/steel core because its now magnetized to oppose the magnet.

 

[Wizkid700]

Btw, when we compare a Solenoid to an Electromagnet. Is the Electromagnet x2 times stronger than the Solenoid?
Can the Solenoid be built in a way to = the Electromagnet?

 

[Skogsgurra]

As I said. I second Bill.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[Wizkid700]

Please do explain.
"I second Bill" wouldn't really help me understand much.

 

[electricpete]

Lets say we had a Solenoid, it can pull/push a magnet without the trouble of having the magnet attracted to the core.
Now, lets we add an iron/steel core. Its magnetized by the current around it. Why should the magnet be attracted to it? Even if the electromagnet is set to push it away. The magnet should be pushed regardless of the iron/steel core because its now magnetized to oppose the magnet.

With core inserted and coil deenergized. Flux from external magnet flows through the core. External magnet is attracted to core.

Apply a very small dc current with polarity to oppose the PM magnet flux. By "small", I mean not enough to reverse the PM-induced flux in the core. The magnet will still be attracted to the core.

Now increase to a large dc current, sufficient to reverse the flux in the core. The magnet will now be repelled.


=====================================
(2B)+(2B)' ?

 

[electricpete]

Sorry, Bill already said that. I didn't read closely.

=====================================
(2B)+(2B)' ?

 

[Wizkid700]

Thank you all for the effort!

 

[Wizkid700]

How much does the ferromagnetic material amplifies the magnetic field of a Solenoid?
Trying to compare between a Solenoid with and without the core.

 

[Skogsgurra]

We do not do designs here. We help with tips. You need to read up on fundamental theory.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[waross]

Get a box of old magnets and play with them. Some will be strong- some may be much weaker. You will find that a the north pole of a strong magnet will attract either pole of a weaker magnet, but the attraction from north pole to south pole will be stronger than the attraction from north pole to north pole.
When calculating the properties of electromagnets, one inch of magnetic path through a core of good transformer iron may be equal to 50,000 inches of magnetic path through air. Some solenoids, the ones used in magnetic contactors come to mind, are built with a small air gap in the magnetic circuit. The purpose is to reduce the flux density so that residual magnetism will not cause the contactor to stick closed.
But this forum is for professionals and you are asking second year electrical apprentice questions.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Wizkid700]

Thank you.