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316L vs 904L

lovethedial

Looking Around
6/12/18
2
3
3
I am starting my own watch manufacturing company. Small Boutique, Swiss movement 2824-2, Sapphire Front glass, My own dial design made here in US. Will be tested and assembled here in US.
Only thing that will be overseas is the hands, and case. Which brings me to question.

316L vs 904L. I have access to both. But the cost for 904L is more, is it worth the added extra cost.

I am trying to keep the MSRP for my watches at 599-799 USD.

Thank you,
 
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irishjohn

Renowned Member
24/11/15
858
90
28
No, i'd stick with 316L

Both of 904L and 316L are Austenite steel which are nonmagnetic and has high corrosion resistant properties, and good machining and polishing performance. As we all know, they can be be regard as substitutes for each other in some cases. So what's the difference?




Grade 316L, the low carbon version of 316, is highly resistant to sensitisation (grain boundary carbide precipitation) and so is extensively used in heavy gauge welded components. The lower carbon content of 316L gives it an even greater resistance to corrosive environments than 316 stainless steel. Austenitic stainless steel 904L is a kind of low carbon high-alloy Austenitic stainless steel with good machinability and weldability and corrosion resistance to dilute sulfuric acid. The addition of copper makes it have strong acid resistance, especially to interstitial corrosion of chloride and stress corrosion.

Chemical Composition is the the key to study and determinate the physical properties of 316L and 904L. We are indicating the chemical composition of the two analyzed SS grades we are studying in the table below.

GradeCMnSiPSCrMo NiCu
316L0.032.00.750.0450.03016.0-18.02.00-3.0010.0-14.0/
904L0.022.01.000.0350.03519.0-23.04.0-5.023.0-28.01.0-2.0




As you can find in the table above, 316L and 904L steel has a similar Chemical composition in the content of C, Si and Mn, but the alloy content such as Chromium, Nickel and Molybdenum of 904L steel is much higher than 1.6 times that of 316L, and 904L steel contains a certain amount of copper, which can effectively delay the corrosion of acidic liquid, especially chloride on stainless steel, making 904L steel more resistant to corrosion and abrasion than 316L. In addition, 904L is much higher resistance to chlorides at elevated temperatures. If 904L has better corrosion resistance, Can I replace 316L with 904L? The answer is No! The higher nickel content of 904L making it is an expensive component and this will influence the overall cost .

There is no difference between 316L and 904L steel in strength and hardness. Both of them have similar Rockwell hardness (HRB) which is less than 95 and their tensile strength are both about 490MPa. These properties are specified for flat rolled product (plate, sheet and coil) in ASTM A240/A240M. The specification for pipe and bar is similar but not necessarily identical properties are specified.
 

csthe

I'm Pretty Popular
16/3/13
1,056
377
0
I am starting my own watch manufacturing company. Small Boutique, Swiss movement 2824-2, Sapphire Front glass, My own dial design made here in US. Will be tested and assembled here in US.
Only thing that will be overseas is the hands, and case. Which brings me to question.

316L vs 904L. I have access to both. But the cost for 904L is more, is it worth the added extra cost.

I am trying to keep the MSRP for my watches at 599-799 USD.

Thank you,
That is sounds like a dream!
can you share (maybe in another post) the process of starting a new watch manufacturing company?
 

wildrabbit

Renowned Member
Supporter
11/8/18
843
175
43
I am starting my own watch manufacturing company. Small Boutique, Swiss movement 2824-2, Sapphire Front glass, My own dial design made here in US. Will be tested and assembled here in US.
Only thing that will be overseas is the hands, and case. Which brings me to question.

316L vs 904L. I have access to both. But the cost for 904L is more, is it worth the added extra cost.

I am trying to keep the MSRP for my watches at 599-799 USD.

Thank you,

As long as you make the Lume Fifty Fathoms or Pelagos -esque, put me down for one.
 
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beau7816

Banned member, the goat does not approve
Banned
20/9/16
6,933
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113
UK Devon
Purchasing watches with 904l steel is not worth the extra big bucks as you really cannot feel or tell the difference despite the ridiculous claims here.
 
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roadtofreedom

Renowned Member
26/12/18
550
267
0
No, i'd stick with 316L

Both of 904L and 316L are Austenite steel which are nonmagnetic and has high corrosion resistant properties, and good machining and polishing performance. As we all know, they can be be regard as substitutes for each other in some cases. So what's the difference?




Grade 316L, the low carbon version of 316, is highly resistant to sensitisation (grain boundary carbide precipitation) and so is extensively used in heavy gauge welded components. The lower carbon content of 316L gives it an even greater resistance to corrosive environments than 316 stainless steel. Austenitic stainless steel 904L is a kind of low carbon high-alloy Austenitic stainless steel with good machinability and weldability and corrosion resistance to dilute sulfuric acid. The addition of copper makes it have strong acid resistance, especially to interstitial corrosion of chloride and stress corrosion.

Chemical Composition is the the key to study and determinate the physical properties of 316L and 904L. We are indicating the chemical composition of the two analyzed SS grades we are studying in the table below.

GradeCMnSiPSCrMo NiCu
316L0.032.00.750.0450.03016.0-18.02.00-3.0010.0-14.0/
904L0.022.01.000.0350.03519.0-23.04.0-5.023.0-28.01.0-2.0




As you can find in the table above, 316L and 904L steel has a similar Chemical composition in the content of C, Si and Mn, but the alloy content such as Chromium, Nickel and Molybdenum of 904L steel is much higher than 1.6 times that of 316L, and 904L steel contains a certain amount of copper, which can effectively delay the corrosion of acidic liquid, especially chloride on stainless steel, making 904L steel more resistant to corrosion and abrasion than 316L. In addition, 904L is much higher resistance to chlorides at elevated temperatures. If 904L has better corrosion resistance, Can I replace 316L with 904L? The answer is No! The higher nickel content of 904L making it is an expensive component and this will influence the overall cost .

There is no difference between 316L and 904L steel in strength and hardness. Both of them have similar Rockwell hardness (HRB) which is less than 95 and their tensile strength are both about 490MPa. These properties are specified for flat rolled product (plate, sheet and coil) in ASTM A240/A240M. The specification for pipe and bar is similar but not necessarily identical properties are specified.

Really good post.

Makes no sense pay +100$ in 904L.

Recently I bought a rep 316L and I couln´t be happier.
 
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Art Tic

Time Machine Collector
26/2/17
948
237
43
California
904L steel has better acidic resistance than 316L steel due to extra Chromium, Molybdenum, Nickel, and Copper elements. So, if the watch wearer tends to sweat a bit more acidic or likes to swim in salt water (ocean), 904L steel case/caseback/bracelet have the obvious advantage. Not an issue if you regularly (and thoroughly) clean your watch. I have older Seiko dive watches from the 70's and 80's that have miniscule corrosion pitting.
 

rolexppapfan

Renowned Member
17/11/18
788
229
43
ITALY
I am starting my own watch manufacturing company. Small Boutique, Swiss movement 2824-2, Sapphire Front glass, My own dial design made here in US. Will be tested and assembled here in US.
Only thing that will be overseas is the hands, and case. Which brings me to question.

316L vs 904L. I have access to both. But the cost for 904L is more, is it worth the added extra cost.

I am trying to keep the MSRP for my watches at 599-799 USD.

Thank you,

Approx. when will we see the watches on the market? ............. will they ship worldwide?
 

lovethedial

Looking Around
6/12/18
2
3
3
Thank you everyone for the positive answers and insight.
I plan to release the first 2 models beginning of 2020.
I will be shipping international.
VMSG: I don’t mind sharing my process so far. Where should I start a thread like that?
 
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Kingsman

Renowned Member
24/11/15
674
92
28
Savile Row
Thank you everyone for the positive answers and insight.
I plan to release the first 2 models beginning of 2020.
I will be shipping international.
VMSG: I don’t mind sharing my process so far. Where should I start a thread like that?

I'd think in the General Discussion or the Gen section. Take a minute to go through the categories and you'll find a good home for your thread. ;)
 

bdhall93

Known Member
5/2/19
135
14
18
Great write up! I had no idea everyone preferred 316 to 904. I was expecting 904 to be the superior hands down. I will be looking for 316 going forward


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beau7816

Banned member, the goat does not approve
Banned
20/9/16
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UK Devon
I would only purchase 904 because of better anti corrosive properties but then lets be realistic do any of us plan to wear the watch on a constant sweaty wrist for 20 or 30 years just to prove a point. I would bet that most of us recycle our watches within 1 to 2 years.....or am i wrong.

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