Difference between 904 steel and 316 steel

[K-R]

I am still curious about the difference in this two type of steel. Anyone have any idea? The difference between 904 and 316 steel?

[BigHat]

Originally Posted by K-R

I am still curious about the difference in this two type of steel. Anyone have any idea? The difference between 904 and 316 steel?

Just google them or do a search TRF. They are just different witches brews of metals in the alloy. Personally, don't think there's much difference in performance in the areas of durability and corrosion resistance. Nickel content is an issue for a few.

Here's a blurb from a comparison between Rolex and Omega reviews. Don't know it's 100 precent correct though.

Tough call here - each has obvious strengths and weaknesses. The SMP feels like a higher quality bracelet. The Sub would seem to be a bit less prone to show scratches. Rolex uses a higher grade steel (904) than Omega (316L) in the bracelet. However, I can discern no functional advantage for them to do so in a watch bracelet, and 904 grade steel is approximate 3 times more expensive than 316L. My research indicates 904 grade steel is more commonly used in industrial components which under constant exposure to highly corrosive substances (acids and the like) - conditions which a watch bracelet simply will not be exposed to. Therefore, there is no appreciable benefit to the 904 grade steel in the Rolex bracelet as compared to 316L used in the Omega bracelet. Indeed, no other watch manufacturer uses 904.

[DSJ]

DO some search on TRF and the WWW - you'll find all sorts of info.

[SSD]

This is probably only a perception, but the 904L seems to be a little more scratch resistant than the 316L. Just an observation, nothing really to back it up. I'm glad the nickel allergy does not affect me, because I like the brighter overall appearance.

I wouldn't want something that corrodes 316L around my bracelet or my wrist anyway

[C. Davidson]

Quick answer:

904L has a higher chromium content (approx. 2x's more) than 316L. Chromium added to steel (Iron and Carbon) changes it from steel into stainless steel. It is the higher chromium content that makes 904L harder and more resistant to corrosion.

Rolex spares no expense when it comes to the quality of their watches.

[Felly Jr.]

A couple things I know is 904 is harder than 316 so therefore is a lot harder to work with. The blades on the machine that punches the cases out need to be replaced a lot quicker than if it were 316 they were punching. Another thing, the 904 is a lot more durable. You can polish and buff out a 904 watch many more times than one with 316 without taking too much metal off. I've got all the stats around here somewhere, just got to find them.

[MrCowboy99]

Originally Posted by K-R

The difference between 904 and 316 steel?

904-316=588 steel?

[Jerico]

I am no expert on this but I have a 7 year old steel date with oyster bracelet that went in for a polish and service. The watch came back looking brand spanking new as if it just came out of the box. Maybe that's the big difference. I wonder if you could do the same with the lesser grade steel. I also tried on an Omega and it just didn't feel as solid as a Rolex. Just my perception...

[Brianm]

Originally Posted by K-R

I am still curious about the difference in this two type of steel. Anyone have any idea? The difference between 904 and 316 steel?

A lot of money!

[f16570]

Perhaps more Rolex marketing hype?

[Ken Cox]

We can look up the properties of 316 and 904 on the internet.

From Azom (A to Z of Materials):

316:

http://www.azom.com/details.asp?ArticleID=2868

904:

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

For those not interested in following the links, 904 has more chromium (26% vs 18%) and less nickel (5% vs 10%) than does 316; and, 904 has the significant addition of copper (2%)

From Azom's site:

"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."

And, Rolex actually uses 904L and not 904.

From Wikipedia:

"Stainless steel is also used for jewellery and watches. The most common stainless steel alloy used for this is 316L. It can be re-finished by any jeweller and will not oxidize or turn black. Not all manufacturers use this type; Rolex for instance use type 904L for their stainless steel watches."

http://en.wikipedia.org/wiki/Stainless_steel

[k4vks]

http://www.rolexforums.com/showthread.php?t=21646

[scottschoe]

http://forums.timezone.com/index.php...03#msg_3782067
http://forums.timezone.com/index.php...8314&rid=26403

[Incurable]

Here's an interesting thread...

http://www.rolexforums.com/showthread.php?t=37095

[Solar]

I really like the Rolex-specific shine of the 904. The first thing that catches my eye on a wrist is the very particular shine of the 904, followed by the Oyster configuration of the bracelet, followed by the unique flat, non-reflective crystal.

Only Rolex has that arrangement of details and it jumps out at me even in a crowd!

Best,

Chris

[golfball123]

thanks... very informative..

[cody p]

Originally Posted by Solar

I really like the Rolex-specific shine of the 904. The first thing that catches my eye on a wrist is the very particular shine of the 904, followed by the Oyster configuration of the bracelet, followed by the unique flat, non-reflective crystal.

Only Rolex has that arrangement of details and it jumps out at me even in a crowd!

Best,

Chris

yeah, 904 does seem to "glow" differently.

[SS Oyster]

Originally Posted by Solar

I really like the Rolex-specific shine of the 904. The first thing that catches my eye on a wrist is the very particular shine of the 904, followed by the Oyster configuration of the bracelet, followed by the unique flat, non-reflective crystal.

Only Rolex has that arrangement of details and it jumps out at me even in a crowd!

Best,

Chris

Thanks for the post, but up until the SDDS, Rolex has not used any anti-reflective coatings on their flat crystals. Only the SDDS uses because of the domed surface. That is what I've read anyway.