Magnetic Properties Difference between Wrought vs Cast

[katiebsmall]

I am looking for into casting parts to save money with the neat net shape however the magnetics of the part are very important to how it operates. Any information on the differences, plus and minus.

Thanks

 

[MagMike]

Information on the material you are using would be helpful...

 

[katiebsmall]

the alloy in question at this time is just plain carbon steel 1020. sorry, forgot to put it in the post.

 

[MagMike]

For a given shape, a wrought piece of steel will have a higher coercivity than an as-cast piece of steel.

What is the applicaiton and how important are the magnetic properties? There is going to be a lot of variablitly since casting/drawing processes are not focused on magnetic properties.

 

[EdStainless]

Mike, really? I have had the opposite experience. We were building test fixtures and the cast ones tended to have slightly lower saturation and higher coercivity. I presume that it was driven by casting chemistry. We ended up tweaking the chem a little to get better magnetic properties.

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Plymouth Tube

 

[MagMike]

Ed, since this request seemed more like a thought experiment I assumed an as-cast block versus one that was cold-worked (wrought). If nothing special was done to the as-cast block, it should have larger grains (= lower coercivity) compared to the wrought. The plastic deformation done to the wrought block would change the grain structuure to produce more pinning sites for the domain walls, thus increasing the coercivity.

Given the lack of details in the request, I gave a generic answer.

Obviously chemistry plays a big role, a block of cast iron with all that carbon will have significantly different properties than 1020 steel. Cooling rate of the cast block (either 1020 steel or cast iron) is very important too.

Of course, I think it is pretty rare to find 1020 steel in the as-cast state.

 

[arunmrao]

My apologies to hijack this thread.

I am looking for information on the magnetic properties of different micro structural phases in steel and their correlation to electron structure. For eg : alpha ferrite and delta ferrite both have bcc structure but different magnetic capacities.Also what are the factors influencing the magnetic capacity of different phases in steel.

Thanks in anticipation.


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"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year

 

[MagMike]

arunmrao[/b/]: Forgive me for asking but how does one obtain delta ferrite at room temperatures? I thought it only occurred at high temperatures.

I suppose alloying may stabilize it for room temperatures, but then those alloying elements would likely influence the magnetic properties.

 

[EdStainless]

I have seen retained delta ferrite in austenitic alloys but never ferritic ones.
I recall that Bozorth talks extensively about the specific properties of various phases. Is this not in enough detail for you?

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Plymouth Tube

 

[arunmrao]

I am just attempting to learn some new aspects about magnetic properties of steels. I have no immediate application for them.

_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year