Determining The Magnetic Saturation of A Soft Iron Magnetic Core

[Yrton]

Hello friends.
I know there a lot of complex mathematic involved in this subject and I'm not currently very knowledgeable in that area but, in simple terms, what would be the simplest way (theoretical or practical) to determine the magnetic saturation of a cylindrical soft iron magnetic core inside an electromagnet? How much magnetic field is needed by the coil in order to saturate this piece?
Here are the dimensions of the core:
diameter = 0.5"
length = 2.5"
Thanks.

 

[berkeman]

Hello friends.
I know there a lot of complex mathematic involved in this subject and I'm not currently very knowledgeable in that area but, in simple terms, what would be the simplest way (theoretical or practical) to determine the magnetic saturation of a cylindrical soft iron magnetic core inside an electromagnet? How much magnetic field is needed by the coil in order to saturate this piece?
Here are the dimensions of the core:
diameter = 0.5"
length = 2.5"
Thanks.

What shape is the core? Is it closed or open? Do you have a datasheet for it? Can you post a picture?

Do you have a bobbin in mind for this core? Do you have a winding machine, or will you be winding the bobbin by hand?

You can use a signal generator and a 2-channel oscilloscope to plot the saturation curve, as long as the signal generator has a low enough output impedance and you can wind enough turns on a test bobbin. If you need more power to saturate the core, you can wire up a simple amplifier circuit to give you a higher current.

What is the core material, and at what frequencies are you going to use it?

 

[Yrton]

What shape is the core? Is it closed or open? Do you have a datasheet for it? Can you post a picture?

Do you have a bobbin in mind for this core? Do you have a winding machine, or will you be winding the bobbin by hand?

You can use a signal generator and a 2-channel oscilloscope to plot the saturation curve, as long as the signal generator has a low enough output impedance and you can wind enough turns on a test bobbin. If you need more power to saturate the core, you can wire up a simple amplifier circuit to give you a higher current.

What is the core material, and at what frequencies are you going to use it?

The core is cylindrical. I'm not sure what you mean by "closed or open". There's no datasheet as I'm designing everything from scratch. No photos available yet.

I have no oscilloscope.

I'm using soft iron for the core. I may want to use a capacitor to create high current.

 

[berkeman]

The core is cylindrical. I'm not sure what you mean by "closed or open".

A cylindrical finite core is open. It is extremely unlikely you will saturate it.

Can you post more about your application? What is the power source? How many turns on the bobbin? What frequency? What is the core material?

 

[berkeman]

I may want to use a capacitor to create high current.

BTW, the verb phrase "wanna" carries negative connotations for some folks. It would be better if you substituted "want to" instead. Just saying...

Also, Is this a DC electromagnet application? Maybe I misinterpreted your OP...

 

[Yrton]

A cylindrical finite core is open. It is extremely unlikely you will saturate it.

Can you post more about your application? What is the power source? How many turns on the bobbin? What frequency? What is the core material?

"Extremely unlikely" but how is the saturation calculated/measure sans the oscilloscopes?
The purpose of this experiment is for me to research and learn about the concept of magnetic saturation in ferrite objects as I wasn't able to find any simplified material regarding this online.
I do not have a specific application for this project in mind. I've already mentioned that the core material is soft iron as it's not very expensive to buy.

 

[berkeman]

"Extremely unlikely" but how is the saturation calculated/measure sans the oscilloscopes?
The purpose of this experiment is for me to research and learn about the concept of magnetic saturation in ferrite objects as I wasn't able to find any simplified material regarding this online.

Ah, so it's more of a learning/academic project, rather than an application. That's totally fine.

It is much more difficult (takes a lot more power) to saturate an open core versus a closed core. An open core includes some of the magnetic path length in air, where the mu is the free space mu. The "reluctance" of the free-space gap is much higher than the reluctance of the magnetic material, so the overall B that you can generate in the magnetic path is much lower.

In a closed magnetic circuit like with a toroid, saturation is much more of a concern for normal circuit operation. There is no gap in the magnetic path, so saturation happens at a lower value of amp-turns excitation.

 

[Yrton]

Ah, so it's more of a learning/academic project, rather than an application. That's totally fine.

It is much more difficult (takes a lot more power) to saturate an open core versus a closed core. An open core includes some of the magnetic path length in air, where the mu is the free space mu. The "reluctance" of the free-space gap is much higher than the reluctance of the magnetic material, so the overall B that you can generate in the magnetic path is much lower.

In a closed magnetic circuit like with a toroid, saturation is much more of a concern for normal circuit operation. There is no gap in the magnetic path, so saturation happens at a lower value of amp-turns excitation.

Thanks for the explanations. I'm still open to get more insights into this subject.