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Guessing the grade of stainless from how it looks? 1
- Thread starter antknee
- Start date
moltenmetal
Chemical
Are you kidding? Surface finish determines colour, not the alloy grade!
- Thread starter
- #3
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1
- #4
moltenmetal
Chemical
If it matters, "look" at the surface with an XRF gun. That will tell you something your eyes are unlikely to see.
- Thread starter
- #5
Try tasting it - that should be more helpful!!!
Steve Jones
Materials & Corrosion Engineer
Steve Jones
Materials & Corrosion Engineer
- Thread starter
- #8
moltenmetal
Chemical
Superman probably doesn't need the XRF gun, or the new teeth for that matter. Then again, he's probably got better uses for his x-ray vision than looking at lumps of stainless!
EdStainless
Materials
In mill products with identical surface conditions you do see color differences, but not enough for identification.
I used to cast alloys and could separate grades by smell, we added S to some and not to others.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
I used to cast alloys and could separate grades by smell, we added S to some and not to others.
= = = = = = = = = = = = = = = = = = = =
Plymouth Tube
MiketheEngineer
Structural
Good luck - like asking where the sugar I had on my cereal came from??
- Thread starter
- #12
Yes - a stainless one.
Steve Jones
Materials & Corrosion Engineer
Steve Jones
Materials & Corrosion Engineer
Is it magnetic? Take a piece of known 304 and a piece of carbon steel and see how strong each pulls. Then try the mystery piece. How strong it pulls in relation to the knowns can give you an idea. If it is strongly magnetic hit it with a grinder to get an idea of the carbon content.
Bob
Bob
- Thread starter
- #16
MiketheEngineer
Structural
How long did it age?? Two days or two hundred years??
Even SS will corrode after a while.
Even SS will corrode after a while.
While not what the OP in interested in, you can, in some instances, tell the grade by looking at it.
For example, take a forging operation that produces the same valve in carbon steel, 410 stainless, and 316 stainless. I could tell by looking at the as-forged valve bodies and determine which was which because of the differenes in the appearance of the scale. Now, this is a result of education and experience so I could spot and understand what caused the scale to take on different appearances, along with knowing that they had to be one of those three grades. This was also years ago; today I might be able to tell if one was A105 or stainless by appearnace, but I wouldn't trust myself.
rp
For example, take a forging operation that produces the same valve in carbon steel, 410 stainless, and 316 stainless. I could tell by looking at the as-forged valve bodies and determine which was which because of the differenes in the appearance of the scale. Now, this is a result of education and experience so I could spot and understand what caused the scale to take on different appearances, along with knowing that they had to be one of those three grades. This was also years ago; today I might be able to tell if one was A105 or stainless by appearnace, but I wouldn't trust myself.
rp
MiketheEngineer
Structural
I challenge you to "eye-ball" ALL grades of SS. Sure - a couple, yes - but after that - good luck
And, I might add, you'll need a lot of luck. My point was that, under controlled situations, it is possible to differentiate between CS, martensitic SS, and austenitic SS. I'd be very suspicious of anyone who said they could tell a 316 from a 321 or a 347 Stainless just by the way it looks.
rp
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