How do I tell stainless steel from silver steel ?

I ordered a number of pieces of 6.35 mm round bar stock in both stainless steel and silver steel which arrived today. Nothing is labelled so how do I tell the difference between the two materials ? I cannot discern any visible difference between them ; it all looks the same to me.

A magnet is the obvious first thing but not all stainless is non magnetic.

Regards.

David

Silver steel is magnetic and the majority of stainless is not.

The silver steel is also likely to be 13" long and the stainless 300mm/12"

Silver steel will go rusty if you leave it out in the rain but thats not teh best way to find out whats what

Edited By JasonB on 29/08/2014 10:59:02

Spark testing may help.

**LINK**

Regards.

David

If you can spare a bit, heat an end of one piece to cherry red and dunk it in cold water. If its too hard to file,its silver steel.If you can,its stainless. I think Jason's suggestion of length would be the best non destructive way of telling.

Brian. Somewhere in the grey matter I think I can remember the same question being asked too many years ago to remember and I was told that stainless steel can be tested with copper sulphate solution. Stainless doesn't take on a copper deposit. Not sure if this applies to the magnetic grades of stainless steel. Perhaps someone can advise on this as I'm not a metallurgist. Something to experiment when I can get some copper sulphate crystals!

Reminds me of those days when I had a Lotts chemistry set!

John

I use Gun Blue for some things so a quick wipe on them would tell them apart. I'm told you can blue stainless steel but the stuff I got from the shop won't touch it!

From a previous thread started by Wolfie on 14/10/2011 "Silver or Stainless" :-

http://www.engineeringtoolbox.com/identification-stainless-steel-d_383.html

has data on identifying different types of stainless. Presumably you know what type of stainless you ordered so the table should tell you if its magnetic and what sort of sparks to expect.

Clive

Just one thing to remember when grinding other metals is don't get the sparks anywhere near the stainless as when they hit it they will weld themselves to the stainless steel and you will then wonder why it is rusting.

Ideally also use a different grinding wheel/cutting disc for stainless as any deposits of ferrous metal embedded in the abrasive can again transfer to the stainless

J

You might also find that your 1/4" stainless is a few tenths of a thou smaller in diameter than the silver steel, that is unless you have bought ground stainless.

Phil

Thank you, the silver steel is magnetic. The stainless is not. They are all slightly different lengths so nothing to go on there.

It is my experience that silver steel apart from being sold in 13in. lengths is always no more than 0.001 ins below size, and mild steel and stainless will normally be 0.002 to 0.003 in smaller at least. Ground stock will usually be spot on for size.

I think the days of Stubs silver steel in 13" lengths are largely gone . The silver steel I've bought of late has been cut off from longer bar.

Cheers,

Rod

Rod, did your silver steel look a bit blue at the end where it was cut, I think it some times gets cut off with an abrasive cutting wheel, then cooled rapidly, leaving a bit at the end dead hard.

Ian S C

I know at least a coupe of suppliers who do imperial in 13" or 39" lengths and metric in 333mm or 1m so its still about. (Make that 3 if you count the classifieds here)

Maybe they are just cutting the longer 39"/1000mm bars down manually to approx 1/3rd

Edited By JasonB on 30/08/2014 14:19:23