Heat Tint/Staining of SS
Heat Tint/Staining of SS
(OP)
Hello all,
I'm new to this site and a relatiely new engineer. I'm working on a project and I was hoping you could help me understand what I am dealing with. I have a 304 SS part (basically no more than a 2' x 2' piece of sheet metal) that is mounted about an inch above a gas heating element. The max. temperature at any point is roughly 1100 F. As expected, portions of the steel have turned blue. I have two questions:
1. What is the mechanism that causes the discoloration?
2. Is this preventable through surface treatments, a different alloy, etc.?
I've read through several threads on the forum, but most questions on this topic had to do with welds.
Thanks in advance,
Michael
I'm new to this site and a relatiely new engineer. I'm working on a project and I was hoping you could help me understand what I am dealing with. I have a 304 SS part (basically no more than a 2' x 2' piece of sheet metal) that is mounted about an inch above a gas heating element. The max. temperature at any point is roughly 1100 F. As expected, portions of the steel have turned blue. I have two questions:
1. What is the mechanism that causes the discoloration?
2. Is this preventable through surface treatments, a different alloy, etc.?
I've read through several threads on the forum, but most questions on this topic had to do with welds.
Thanks in advance,
Michael





RE: Heat Tint/Staining of SS
2) Insulation
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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
RE: Heat Tint/Staining of SS
RE: Heat Tint/Staining of SS
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/
RE: Heat Tint/Staining of SS
RE: Heat Tint/Staining of SS
Higher Cr SS grades will discolor but suffer less damage over time from the oxidation.
You need to know if the heating is constant or cyclic before selecting an alloy.
If this is near a flame you also need to be concerned about other products of combustion (SOx and NOx).
All metals will discolor, but some will last much longer than others.
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Plymouth Tube
RE: Heat Tint/Staining of SS
Just for clarification, Compositepro is referring to porcelain enamelled steel. It is a hard ceramic coating, such as that found on older steel bathtubs. It's a good suggestion if discoloration is not acceptable for your application.
RE: Heat Tint/Staining of SS
Equipment which is enamelled (glass lined) for corrosion resistance has temperature limits much lower than 1100 F and is quite sensitive to thermal shock even within that lower temperature range.