904L Steel

[burger'n'fries]

I got my first and hopefully last ding on my watch. It was a simple mistake; I tossed my Explorer on my bed and it came into contact with my iPhone 4. I thought the impact was minimal until I noticed a couple on small indentations on one of the case lugs. Apparently, the watch case hit the stainless steel band on the iPhone. I inspected the phone and found nothing. This led me to think about about the hardness or toughness of 904L steel.

Is 904L steel too soft?

Does Rolex temper or heat treat their stainless steel components?

What do you guys think?

Also, on a lighter note, ever since a bought my Explorer my fiancé has been eyeballing my watch with some envy even though she doesn't really know the Rolex brand. She does know however, the Tiffany & Co. brand to my wallet's dismay. Anyway, I thought I would surprise her; gave it to her a couple days ago. It's a discontinued ref. 76080 that I got a good deal on. She's real happy. Though I've only seen her wear it once (the day she got it)...

[ObscureLight]

Wow you have a sturdy iPhone then. My first iPhone 4 developed random dents on the band and I had to go do an exchange for a new one

[Sunshine]

904L is a non-stabilised low carbon high alloy austenitic stainless steel. The addition of copper to this grade gives it greatly improved resistance to strong reducing acids, particularly sulphuric acid. It is also highly resistant to chloride attack - both pitting / crevice corrosion and stress corrosion cracking.
This grade is non-magnetic in all conditions and has excellent weldability and formability. The austenitic structure also gives this grade excellent toughness, even down to cryogenic temperatures.
904L does have very substantial contents of the high cost ingredients nickel and molybdenum. Many of the applications in which this grade has previously performed well can now be fulfilled at lower cost by duplex stainless steel 2205 (S31803 or S32205), so it is used less commonly than in the past.
Key Properties
These properties are specified for flat rolled product (plate, sheet and coil) in ASTM B625. Similar but not necessarily identical properties are specified for other products such as pipe, tube and bar in their respective specifications.
Composition


Table 1. Composition ranges for 904L grade of stainless steels.
Grade C Mn Si P S Cr Mo Ni Cu
904L min.
max. -
0.020 -
2.00 -
1.00 -
0.045 -
0.035 19.0
23.0 4.0
5.0 23.0
28.0 1.0
2.0

Mechanical Properties

Table 2. Mechanical properties of 904L grade stainless steels.
Grade Tensile Strength (MPa) min Yield Strength 0.2% Proof (MPa) min Elongation (% in 50mm) min Hardness
Rockwell B (HR B) Brinell (HB)
904L 490 220 35 70-90 typical -
Rockwell Hardness value range is typical only; other values are specified limits.
Physical Properties

Table 3. Typical physical properties for 904L grade stainless steels.
Grade Density
(kg/m3) Elastic Modulus
(GPa) Mean Co-eff of Thermal Expansion (µm/m/°C) Thermal Conductivity
(W/m.K) Specific Heat 0-100°C
(J/kg.K) Elec Resistivity
(nΩ.m)
0-100°C 0-315°C 0-538°C At 20°C At 500°C
904L 8000 200 15 - - 13 - 500 850
Grade Specification Comparison


Table 4. Grade specifications for 904L grade stainless steels.
Grade UNS No Old British Euronorm Swedish SS Japanese JIS
BS En No Name
904L N08904 904S13 - 1.4539 X1NiCrMoCuN25-20-5 2562 -
These comparisons are approximate only. The list is intended as a comparison of functionally similar materials not as a schedule of contractual equivalents. If exact equivalents are needed original specifications must be consulted.
Possible Alternative Grades


Table 5. Possible alternative grades to 904L stainless steel.
Grade Why it might be chosen instead of 904L
316L A lower cost alternative, but with much lower corrosion resistance.
6Mo A higher resistance to pitting and crevice corrosion resistance is needed.
2205 A very similar corrosion resistance, with the 2205 having higher mechanical strength, and at a lower cost to 904L. (2205 not suitable for temperatures above 300°C.)
Super duplex Higher corrosion resistance is needed, together with a higher strength than 904L.
Corrosion Resistance
Although originally developed for its resistance to sulphuric acid it also has a very high resistance to a wide range of environments. A PRE of 35 indicates that the material has good resistance to warm sea water and other high chloride environments. High nickel content results in a much better resistance to stress corrosion cracking than the standard austenitic grades. Copper adds resistance to sulphuric and other reducing acids, particularly in the very aggressive "mid concentration" range.
In most environments 904L has a corrosion performance intermediate between the standard austenitic grade 316L and the very highly alloyed 6% molybdenum and similar "super austenitic" grades.
In aggressive nitric acid 904L has less resistance than molybdenum-free grades such as 304L and 310L.
For maximum stress corrosion cracking resistance in critical environments the steel should be solution treated after cold work.
Heat Resistance
Good resistance to oxidation, but like other highly alloyed grades suffers from structural instability (precipitation of brittle phases such as sigma) at elevated temperatures. 904L should not be used above about 400°C.
Heat Treatment
Solution Treatment (Annealing) - heat to 1090-1175°C and cool rapidly. This grade cannot be hardened by thermal treatment.
Welding
904L can be successfully welded by all standard methods. Care needs to be taken as this grade solidifies fully austenitic, so is susceptible to hot cracking, particularly in constrained weldments. No pre-heat should be used and in most cases post weld heat treatment is also not required. AS 1554.6 pre-qualifies Grade 904L rods and electrodes for welding of 904L.
Fabrication
904L is a high purity, low sulphur grade, and as such will not machine well. Despite this the grade can be machined using standard techniques.
Bending to a small radius is readily carried out. In most cases this is performed cold. Subsequent annealing is generally not required, although it should be considered if the fabrication is to be used in an environment where severe stress corrosion cracking conditions are anticipated.
Applications
Typical applications include:
• Processing plant for sulphuric, phosphoric and acetic acids
• Pulp and paper processing
• Components in gas scrubbing plants
• Seawater cooling equipment
• Oil refinery components
• Wires in electrostatic precipitators

My company has used this material in areas were high amounts sulphuric acid is present. In petro. Chems. We will overlay sulphur reactors with a ER904L weld wire for corrosion protection.

[ersnyder]

Ouch! That is one tough I Phone!!

[burger'n'fries]

Hey Sunshine,

You may have a degree in metallurgy, but I have a BA in English from UCLA which means I've spent four years of my life researching, analyzing, and remembering what other people have written before me and PLAGIARISM is unethical and unacceptable in my book.

http://www.azom.com/details.asp?ArticleID=1022

You could have tried to be a little original or creative, but word for word your post is identical to the one mentioned above. If you're going to use someone else's hard work you should've at least given credit to the actual author instead of trying to pass it off as your own.

Also, for your information I didn't ask about the anti-corrosive properties of 904L steel. I asked whether or not if any TRF members thought 904L steel was too soft based on similar experiences and I asked if Rolex treats their steel. I asked for opinions NOT for an irrelevant response stolen from the internet.

If by some marginal chance you created that website and are the actual author of that information I sincerely apologize. If not, please do not respond to any of my future inquiries...ever.

[padi56]

Originally Posted by burger'n'fries

I got my first and hopefully last ding on my watch. It was a simple mistake; I tossed my Explorer on my bed and it came into contact with my iPhone 4. I thought the impact was minimal until I noticed a couple on small indentations on one of the case lugs. Apparently, the watch case hit the stainless steel band on the iPhone. I inspected the phone and found nothing. This led me to think about about the hardness or toughness of 904L steel.

Is 904L steel too soft?

Does Rolex temper or heat treat their stainless steel components?

What do you guys think?

Also, on a lighter note, ever since a bought my Explorer my fiancé has been eyeballing my watch with some envy even though she doesn't really know the Rolex brand. She does know however, the Tiffany & Co. brand to my wallet's dismay. Anyway, I thought I would surprise her; gave it to her a couple days ago. It's a discontinued ref. 76080 that I got a good deal on. She's real happy. Though I've only seen her wear it once (the day she got it)...

Well I suppose its how hard you tossed your watch and from what height,the heavier it is the harder it will fall.And the ding right on the edge steel hitting steel, would doubt if it would have made any difference whatever s.steel 904L or 316L the ding would have been the same.

[Sunshine]

Originally Posted by burger'n'fries

Hey Sunshine,

You may have a degree in metallurgy, but I have a BA in English from UCLA which means I've spent four years of my life researching, analyzing, and remembering what other people have written before me and PLAGIARISM is unethical and unacceptable in my book.

http://www.azom.com/details.asp?ArticleID=1022

You could have tried to be a little original or creative, but word for word your post is identical to the one mentioned above. If you're going to use someone else's hard work you should've at least given credit to the actual author instead of trying to pass it off as your own.

Also, for your information I didn't ask about the anti-corrosive properties of 904L steel. I asked whether or not if any TRF members thought 904L steel was too soft based on similar experiences and I asked if Rolex treats their steel. I asked for opinions NOT for an irrelevant response stolen from the internet.

If by some marginal chance you created that website and are the actual author of that information I sincerely apologize. If not, please do not respond to any of my future inquiries...ever.

I am sorry if you do not know how a chemical composition in metallurgy is formed. But if you will continue to research the “word for word” info. is listed in Seimens, GE thermal, Black and Veach and Atlas Steel back ground as well as a few others. This is pulled from other ASME AWS and NBIC publications and has been for about 30 years. This keeps people from adding their own twits to the subject. As for the site you found it is pulled from the Atlas Steel site and my company dose work for them on a regular base. I am sorry for any confusion.

[esm]

Originally Posted by burger'n'fries

Hey Sunshine,

You may have a degree in metallurgy, but I have a BA in English from UCLA which means I've spent four years of my life researching, analyzing, and remembering what other people have written before me and PLAGIARISM is unethical and unacceptable in my book.

http://www.azom.com/details.asp?ArticleID=1022

You could have tried to be a little original or creative, but word for word your post is identical to the one mentioned above. If you're going to use someone else's hard work you should've at least given credit to the actual author instead of trying to pass it off as your own.

Also, for your information I didn't ask about the anti-corrosive properties of 904L steel. I asked whether or not if any TRF members thought 904L steel was too soft based on similar experiences and I asked if Rolex treats their steel. I asked for opinions NOT for an irrelevant response stolen from the internet.

If by some marginal chance you created that website and are the actual author of that information I sincerely apologize. If not, please do not respond to any of my future inquiries...ever.

wow - talk about being unappreciative of other people's kind help (im sure Jim (aka. Sunshine) did not intend to make that whole post has his own research)

this is an open forum - you asked questions, so the chances are, you will get all sorts of answers.

[padi56]

Right gentlemen lets all calm down and take a chill pill.

[Brushpup]

Honestly, what I think is that you oughta be a little more careful with your watch. But to answer your question, no it isn't too soft in my view.

Finally I agree the same would have happened to a case made of other SS varieties, and worse with gold.

[Sunshine]

Originally Posted by esm

wow - talk about being unappreciative of other people's kind help (im sure Jim (aka. Sunshine) did not intend to make that whole post has his own research)

this is an open forum - you asked questions, so the chances are, you will get all sorts of answers.

In my field this info. Is the same everywhere. Not only for 904 but 316L,309,347,308, 321.. I could go on forever. I would have posted it “not my words” but this is such a common use in my field the thought did not cross my mine. Thank you for the back-up

[slevin kelevra]

Im very careful with my watch and it has lots of little scracthes and dings on it. Dont worry too much about it.

[Johny]

hi sunshine. considering the amount of discussion on stainless we get on the forum its good to know that we have someone with a degree in metallurgy as a member. johny.

[Gob Bluth]

Plagiarism. Is that a joke? Relax English major. Lamest post I've ever seen on trf.

[Captainz]

I remember two things I read about 904L:

1) Extremely Corrosion Proof. If you get a scratch, it automatically fills it in to prevent corrosion.<---Main benefit

2) Rolex uses a 250 ton press to form out the bracelet. So yes it is very tight and strong.

Keep it simple, thats my motto!

Al

[cht]

Originally Posted by Sunshine

I am sorry if you do not know how a chemical composition in metallurgy is formed. But if you will continue to research the “word for word” info. is listed in Seimens, GE thermal, Black and Veach and Atlas Steel back ground as well as a few others. This is pulled from other ASME AWS and NBIC publications and has been for about 30 years. This keeps people from adding their own twits to the subject. As for the site you found it is pulled from the Atlas Steel site and my company dose work for them on a regular base. I am sorry for any confusion.

OP just got served....



But to contribute, is it possible those small marks were there before and the iphone incident prompted you to closely inspect the watch?

[Route 66]

Originally Posted by Captainz

Extremely Corrosion Proof. If you get a scratch, it automatically fills it in to prevent corrosion.<---Main benefit

Al

I'd love to know how this works...

It's sounds as if it can heal itself like...skin.

[Captainz]

Originally Posted by Stevarn

I'd love to know how this works...

It's sounds as if it can heal itself like...skin.

Steve,

Here u go:

"In the event of a scratch, the chromium-oxide barrier fills and protects it immediately, effectively reducing the scratch's propensity to corrode."

Al

[Route 66]

Originally Posted by Captainz

Steve,

Here u go:

"In the event of a scratch, the chromium-oxide barrier fills and protects it immediately, effectively reducing the scratch's propensity to corrode."

Al

Thanks Al, but I still don't understand how this is possible.

[Captainz]

Originally Posted by Stevarn

Thanks Al, but I still don't understand how this is possible.

Steve,

Here u go:

"904L steel has a higher chromium content than standard steel. The chromium forms a thin, impervious barrier on the alloy's surface when exposed to oxygen. In the event of a scratch, the .........."

Al

[Route 66]

Originally Posted by Captainz

Steve,

Here u go:

"904L steel has a higher chromium content than standard steel. The chromium forms a thin, impervious barrier on the alloy's surface when exposed to oxygen. In the event of a scratch, the .........."

Al

Thanks again Al, That's simply AMAZING to me! WOW!!

[Z_Z]

Originally Posted by burger'n'fries

Hey Sunshine,

You may have a degree in metallurgy, but I have a BA in English from UCLA which means I've spent four years of my life researching, analyzing, and remembering what other people have written before me and PLAGIARISM is unethical and unacceptable in my book.

http://www.azom.com/details.asp?ArticleID=1022

You could have tried to be a little original or creative, but word for word your post is identical to the one mentioned above. If you're going to use someone else's hard work you should've at least given credit to the actual author instead of trying to pass it off as your own.

Also, for your information I didn't ask about the anti-corrosive properties of 904L steel. I asked whether or not if any TRF members thought 904L steel was too soft based on similar experiences and I asked if Rolex treats their steel. I asked for opinions NOT for an irrelevant response stolen from the internet.

If by some marginal chance you created that website and are the actual author of that information I sincerely apologize. If not, please do not respond to any of my future inquiries...ever.

Where did that come from? I think you should apologize to Sunshine for your irrational outburst.

[Mr. Bond]

Originally Posted by Gob Bluth

Plagiarism. Is that a joke? Relax English major. Lamest post I've ever seen on trf.

Agreed! Was he expecting a bibliography at the end of the post? Who doesn't copy and share information over the Internet from time to time? It's not like he was writing a term paper

[TSts]

I believe that the 904L steel used for the case and bracelet is in it's soft, annealed form. Not heat treated or tempered.

I use different kinds of SS for the instruments the company I own produces. I know my metals, however, I wont pull a Sunshine - no where, in his initial reply to the OP, does it give an answer to his question.

[padi56]

Originally Posted by Captainz

I remember two things I read about 904L:

1) Extremely Corrosion Proof. If you get a scratch, it automatically fills it in to prevent corrosion.<---Main benefit

2) Rolex uses a 250 ton press to form out the bracelet. So yes it is very tight and strong.

Keep it simple, thats my motto!

Al

Originally Posted by Captainz

Steve,

Here u go:

"In the event of a scratch, the chromium-oxide barrier fills and protects it immediately, effectively reducing the scratch's propensity to corrode."

Al

Originally Posted by Captainz

Steve,

Here u go:

"904L steel has a higher chromium content than standard steel. The chromium forms a thin, impervious barrier on the alloy's surface when exposed to oxygen. In the event of a scratch, the .........."

Al

Of course Rolex portrays 904L as "Super Alloy"but the main difference between 316L over 904L it has slightly more Molybdenum(Mo)approx 2% more, approx 1-2% more Crome(Cr) 1% copper(Cu) and approx 10% more nickel and thats it, just slightly chemically different, its no harder or tougher than 316L when tempered 316L could be harder.And today most Rolex watches get a very very pampered life so it does not really matter what material its made from, in say 85%-90% of everyday wearers.Its quite simple as long as any watch is rinsed in fresh water after exposure to salt water and kept clean serviced in its life.the watch will last for decades no matter what the grade S.steel.I have a Rolex Unicorn from 1922 one of the first S.steel watches,and at this time S.steel was more expensive than silver.The case and movement are still fine wish I could say the same for the dial and hands.

[Route 66]

Hey Jim (Sunshine), I think you struck a nerve with people because your post began with "Well I have a degree in metallurgy so!!!! This gave the strong impression that what followed was your thoughts based on your expertise in metallurgy.

Just my

[ObscureLight]

I think this thread has been blown totally outta proportion!!!

[jeremyam]

I don't know much about metals and the only difference that I can take away from this forum and other is that 316L is cheaper and less resistant to corrosion. By corrision, I mean exposure to chemicals, elements that would destroy your skin, so it's a good thing to know that if you're hand is falling off your wrist, your Rolex will be A ok, another note-worthy benefit to owning a Rolex.

Redonkulousness.

[ajay_sharma007@yahoo]

pls tell me which rolex watch is produced in 904L first

[GradyPhilpott]

Originally Posted by Gob Bluth

Plagiarism. Is that a joke? Relax English major. Lamest post I've ever seen on trf.

Plagiarism isn't a joke, although I agree that the response to the post was over the top.

I think this line answers the OP's question amply.

Originally Posted by Sunshine

The austenitic structure also gives this grade excellent toughness, even down to cryogenic temperatures."

A simple link to the source material should be included and complete copy and pasting should be discouraged.

It's just bad form and websites have been sued for such. I am a member of such a site, so I know for a fact that it can happen.