How can you grade stainless steel ?

[waynieZ]

There's a guy near me that has a sheet of Stainless steel for sale. Is there a way to tell what grade it is?? He has no idea. If as magnet doesn't stick to it does that mean its at least 304, or that doesn't matter? I have no idea of what to check. Any help will be appreciated.
Thanks

[billetman]

Wayne, Most grades of stainless steel are non magnetic. 400 series is magnetic where the 300 series usually is not. 304 ss is used widely where corrosion resistance is a prime consideration,such as exhaust pipe and mufflers. 400 series will eventually form a coating of rust after several heating and cooling cycles such as OEM and aftermarket headers,pipe and mufflers. 304ss lends itself well to welding applications also. If machining is a consideration 303 grade is considered the best due to its increased lead content,but there is 304L grade that contains alot of lead and is good for machining purposes also. Metal suppliers most often offer ss sheet in 304 grade so its a safe bet that the sheet you have obtained is just that. Hope this helps. Jeff

[waynieZ]

Thanks Jeff; This is a sheet that I was thinking of using for a fuel tank. A while ago a friend offered to weld up a tank for me so I was thinking with that in mind. Here's the discription he sent me 44"X38"x 1/16" steel plates with a chrome finish. He also has some in 1/8' thick.