Non-magnetic Stainless Steel?

I am not up on the tecno data, but I thought all stainless steel is non-magnetic.

I believe it has to do with the chromium content, but I am not sure what percentage of chromium is required.

All steel is magnetic up to a certain degree, but some stainless is less magnetic.

Do a google:

http://www.azom.com/details.asp?ArticleID=1140
http://www.smalley.com/help/MaterialSelectionGuideHelp.asp

Basically, even the less magnetic stainless steels can become magnetic once they are worked.

Chromium is the element that make`s stainless steel stainless or corotion resistant. Stainless steels are iron-chromium alloys (most have a low carbon content) that contain at least 11% chromium. The level is the content at which effective resistance to atmospheric corrosion begins. Other compositions , Nickle, Manganese, Molybdenum, Silicone, Sulfer.

Remember Stainless has many different types 200,300,400 each series has several different types say 301,302,302b,304,304l,305,308, ext. ext. all have a diferent makeup for many different applications. Stainless, brass,aluminium all are non ferrous or non magnetic family even thought they do have a little iron content. As Riffer said stainless can become magntic once worked at once cold worked and would need to be annealed to be brought back to a non magnetic state. David

All solid steel based antennas are non-magnetic, otherwise their conductivity and radiation characteristics would be far less predictable than they are. Sean
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Riffer, thanks for those URL's, and my education! I only have had experience with stainless steel used for other than electronic purposes. I collected knives at one point, so I'm familiar with various types of steel. I checked, and all of my stainless steel blades ARE magnetic. Actually, did you know that a high carbon steel blade will hold a better edge than a stainless steel blade?

Sean, I'm going to have to carry a magnet with me, and check out those solid steel car antennas...hope that I don't get arrested for attempted auto theft :-)

FP: I don't know if factory car antennas are ferrous or non-ferrous. I was primarily talking about about aftermarket RF antennas when i made that comment. I would be curious to find this out myself. I'll test mine and let you know tomorrow : ) Sean
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300 series stainless is non magnetic, while 400 series IS magnetic. I think it has to do with whether or not there is any nickel content.

Trivia - stainless steel was discovered at a plant in northern Indiana. Test alloys were stored outside, one day a janitor got curious and asked why a particular piece of steel that had been out in the weather for quite a while wasn't rusted. Doubt that his name made it on the patent though.
Ok not audio related, just always thought it was a neat story.

Carefull, what people think is stainless steel is often just chrome electroplated steel. Ex. some cutlery and antennae on automobiles. That might explain the "magnetic" qualities of some "stainless steels". It is mostly the nickel in stainless steel that give it its "non-corrosion" properties. Nickel is non-ferrous (obviously!) and non-magnetic.

Bob P.