Which stainless steels are Magnetic
I always thought that stainless steel wasn't magnetic. My friend told me the other day that it was, so we tested all different kinds of metals, with a magnet, to find out. Some were and some weren't magnetic. How many types of stainless do they have? Which ones are magnetic?Jace Duncan
- Ruston, Louisiana
For stainless steels, it depends on the structure- the pattern of atomic arrangement. Body centered cubic (ferritic 400 series) and body centered tetragonal (martensitic 400 series, PH grades) are ferromagnetic, meaning they are attracted to a magnet. Face centered cubic (200 and 300 series) are USUALLY not ferromagnetic, and aren't attracted. One of the caveats is that cold working, like the kind necessary to get 302 sheet really flat and smooth will cause the FCC structure to go to BCT, and will make it ferromagnetic. Hence some stainless steel appliances are magnetic, some aren't.
By the way, the American Iron and Steel Institute, who first came up with the numbering system I've mentioned, recognizes over 80 different grades of stainless steel. Go to the Nickel Development Institute at nidi.org and have them mail you a copy of publication 9014 if you really want to know about stainless steel.
September 9, 2009
I am not sure what is going on, but maybe someone knowledgeable will be able to help.
The problem is that I have a SIGG bottle (canteen), stainless steel, 18/8 -the top and some middle part is being attracted by my strong neodymium magnet, but the lower half of the bottle and the bottom itself is not, at all! The same thing happens to a 'HomePresence' 18/10 stainless steel desk mug -but this one is not being attracted at all on any sides.
Why would company differ ore composition or there is something else I should know?
student - Wisconsin
September 10, 2009
Hi, Alex. Instead of launching a new thread, we appended your question to a thread which already answers it. Let us know if the answer is not clear.
Ted Mooney, P.E. RET
Brick, New Jersey