Heat treat for electrical applications

[bdunlap]

I am working on an electromagnetic application and will be testing some parts that I made out of Alloy 50 and 12L14.

I found a heat treatment schedule from Carpenter for the Alloy 50:

"Anneal parts at 1300/1600 °F for 2-4 hours in dry hydrogen or vacuum and cool at 150/350°F per hour until 600°F is reached, after which any cooling rate can be employed"

Does anyone know the heat treatment for 12L15 that would produce soft magnetic properties?

Thanks!

 

[israelkk]

What magnetic application?

 

[EdStainless]

Optimizing permeability and saturation are two different issues.

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Plymouth Tube

 

[bdunlap]

To clarify, permeability is my area of focus. I am already planning on heat treating the alloy 50 and since I didn't know of any particular heat treating for the 12L14 I was thinking of including it in the batch with the alloy 50... Unless anyone knows of a more optimal heat treatment for the 12L14 that would optimize its permeability.
Thanks!

 

[israelkk]

No magnetic properties is guarantied for 12L14. You can not trust your results for other batches/heat lots of the material. It is a free machining low alloy carbon steel for mechanical uses. If permeability consistency is you goal then forget 12L14.

 

[EdStainless]

So what happens when the lead melts?

You may get nice saturation out of your 12L15 but don't expect good perm numbers.
In order to get perm in iron you need it clean. We used to anneal overnight in hydrogen at 2650F in order to lower the the C, S, and O. We started with Armco A and then when it wasn't available we went to 1001/1002.
Your 1600F for 4 hours in hydrogen is a good start and will probably give you all that you can expect our of 1215.


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Plymouth Tube

 

[bdunlap]

Thanks for the input. I made a mistake and got my spec sheets mixed up and posted the heat treatment for Hiperco Alloy 50 which is a 48.75% Cobalt.

Alloy 49 with 48% Ni has the following heat treat:

"For maximum softness and optimum magnetic and electrical properties, Carpenter High Permeability "49" alloy should be annealed in an oxygen-free, dry hydrogen atmosphere with a dew point below -40°F (-40°C) for 2 to 4 hours at 2150°F (1177°C), followed by a furnace cool at a rate of 100/200°F (38/93°C) per hour down to 800°F (427°C) and at any rate thereafter"

http://candcmachininginc.com/CarpenterDatasheet.PDF