Slightly magnetic Steels

What magentic property are you asking about?

Austenitic SS like 304,316,301 etc becom more and more attracted to a magnet depending on the amount of cold work that is done to them. Somewhere Somewhen someone probably did a study relating %CW (%reduction) to ferro-magnetism.

There are other magnetic properties like permeability etc that I'm not able to answer on IE I dont know about.

nick

In addition to NickE's comments, cast austenitic stainless steels are typically slightly ferromagnetic. Duplex stainless steels are also ferromagnetic based on the ferrite:austenite balance.

By the way, do you mean ferromagnetic or magnetic (having the properties of a magnet?

One way to get a range of differing ferrite contents, and thus differing magnetic permeability would be to use stainless steel welding rod. You can get austenitic stainless with ferrite from nothing to approx 30% or duplex stainless with 30-60% depending on the type/chemical compositions. A lot of manufacturers list the expected ferrite content in their literature. You could also modify the ferrite content by welding over different base metals, such as mild steel, stainless steel, and using different perameters and number of layers.

In order to get a magnetic stainless steel you'll have to get a 400 series, such as 410SS or 416SS. Their Fe contents are above 50% which allows them to be attracted to a magnet. The 300's are less than that and are not magnetic. Visit - you can look these metals up here.

Here a couple of good websites that you may want to look at for additional information.

Some manetic alloys

Soft Magnetic alloys

Different magnetic alloys.

I guess ferromagnetic is the key word. I would like magnets to have a mild attraction to them. I am interested in buying different sheet stocks with varying ferromagnetic properties. I have one SS sheet that is quite ferromagnetic. I'll assume this is a 400 series. I also have another piece that is only very slightly ferromagnetic. Although you it was said that 300 series are non-magnetic, I'm inclined to believe it may have been a 300 series... perhaps 316? The magnets I'm using are NdFeB, and pull at 12,000 gauss.... I believe they're pretty much the strongest magnet available. And believe me, they're STRONG. Anyway, I'm not sure a full 50% Fe content is necessary in the steel for these particular magnets to have an attraction. I'm guess anything 20%-30% Fe content would register. Thank you for all your replies. This is the fastest response I've ever gotten.

Aaron Spearin, EIT
ChemE, M.E.
"The only constant in life is change." -Dan Andia; 1999, Chemical Engineering Progress

As NickE stated earlier, all you have to do is find/buy some 300 series SS with different amounts of cold work. When cold worked a lot, 304 SS will attract your magnet so hard you'll need a crowbar to get it off.

You might want to contact these people as they have several tempers of SS stock.
They were quite helpful to me several times.

Is it a rule of thumb that the higher # grade, the higher the iron content?

Aaron Spearin, EIT
ChemE, M.E.
"The only constant in life is change." -Dan Andia; 1999, Chemical Engineering Progress

No. The grade numbers of 300 series SS does clearly reflect the composition but really has no correlation with the Fe concentration. A case in point 310 SS has less Fe than 316 SS. You will have to get a table of compositions to get the Fe concentrations.