304L vs 316L

[velorossa22]

Just wondering what everyone has found in terms of the difference between the 2 grades of stainless. I have been using 304L without any corrosion and any noticable ill effects. Has anyone done any testing between the outputs between the 2? I wonder if the 316L has different resistance ( like maybe lower) so that it would better output. 304L is way cheaper so if there really isn't any difference then why not use 304L? Something to think about.:D

[velorossa22]

I read that 316 has more nickel and less chromium than 304. Molybdenem is only .5% for 304 and 2.5-3.5% for 316. There is no difference in machinability, weldability and particle generation and vacuum properties. The only difference is in how well it holds up in a corrosive environment.
Here's the link if you don't believe me:
http://www.mksinst.com/docs/ur/tubing.pdf
So the question is to all those using wall plates and 304L stainless has anyone had the plates deteriorate in the electrolyte?:rolleyes:

[H2OPWR]

I read that 316 has more nickel and less chromium than 304. Molybdenem is only .5% for 304 and 2.5-3.5% for 316. There is no difference in machinability, weldability and particle generation and vacuum properties. The only difference is in how well it holds up in a corrosive environment.
Here's the link if you don't believe me:
http://www.mksinst.com/docs/ur/tubing.pdf
So the question is to all those using wall plates and 304L stainless has anyone had the plates deteriorate in the electrolyte?:rolleyes:

The big difference is the low carbon content. That is what really helps. 316L is much better over the long haul.

Larry

[velorossa22]

Right I agree that 316 would last longer, but how much? Has anyone used both and found data on the lifespan of each one? I mean if 316 lasts twice as long but 304 costs a quarter as much doesn't it make 304 cheaper in the long run? Just food for thought.
Also how can a person verify the grade of stainless if it's not printed on the metal. Aren't people just depending on the honesty of others?:confused: People sell dry cell generators on ebay with 21 6x6 SS 316L plates for around a $100 :eek:. I would think they got more into the plates than $100.

[H2OPWR]

Right I agree that 316 would last longer, but how much? Has anyone used both and found data on the lifespan of each one? I mean if 316 lasts twice as long but 304 costs a quarter as much doesn't it make 304 cheaper in the long run? Just food for thought.
Also how can a person verify the grade of stainless if it's not printed on the metal. Aren't people just depending on the honesty of others?:confused: People sell dry cell generators on ebay with 21 6x6 SS 316L plates for around a $100 :eek:. I would think they got more into the plates than $100.

The sad news is that you can not tell the difference between the two. Even the local stainless supplier can not tell once the protective coating is removed unless it is printed on the steel itself.

Yes I would not spend my $100.00 on a device off ebay that they claim to have 21 6X6 316L plates in. The plates would cost that or close alone without everything else.

Larry

[Zolar1]

Get a magnet. 304 is drawn to a magnet quite powerfully.

A magnet doesn't attract 316L. (sometimes, you might get a very slight pull, depending on how strong your magnet is)

316L has less ferrous in it than 304/308 grades.

[H2OPWR]

Get a magnet. 304 is drawn to a magnet quite powerfully.

A magnet doesn't attract 316L. (sometimes, you might get a very slight pull, depending on how strong your magnet is)

316L has less ferrous in it than 304/308 grades.

Sorry but you are mistaken. 304 is not magnetic. 430 is magnetic. Neither 304 or 316 SS is magnetic. I was at the stainless suplier recently and they admit that in a scrap bin there is no way to tell the difference.

Larry

[velorossa22]

I've never heard of 308 grade. Is there such a thing?

[NightOfDarkness]

I believe you could tell the difference after you run your cell if its 316L your water will stay clean/clear anything less will turn your water brown. Youll know after you run your cell for few hours

or buy a spot test kit very pricey
http://www.koslow.com/304vs316.html

http://www.elmerwallace.co.uk/Stainless-Steel-Identification-Test-kits/C10-1-0.htm


Ohh and I sell 21 plates 316L 6x6 $160

[NightOfDarkness]

I've never heard of 308 grade. Is there such a thing?


Yes there is 308 and 309 and 310 etc...

http://www.engineeringtoolbox.com/identification-stainless-steel-d_383.html

[rboos]

I guess 316L (surgical grade SS) must have better conductivity (there is a comparative table under electrode types thread) and resists oxidation.

[Mrx99]

I worked in the pipe fitting industry for quite a few years and 304 stainless has iron in it. 316 stainless does not have iron in it so a magnet should be able to pick out the 304 stainless. when you get into the 400's with stainless you are getting into the purer state of stainless. I am not positive but I think the 400 grades are for medical use. Some prosthesis's are made from 408 or a number similar to it. I worked at a nuclear plant and some of the stainless was in the high 400's. When you are using stainless around fuel rods it has to be free of impurities. We could not use any iron tools to work on the stainless because of contamination.
So, I think the iron in 304 stainless will come out as brown water the first time and perhaps the first year of using 304 stainless steel plates. Because of the ferrous metals in the 304 the process of electrolysis would not work as well as 316 stainless.
Thanks, Mrx

[Mrx99]

308 is the number of the filler rod used to weld 304 and 309 is used to weld 316 stainless steel. You can weld stainless to carbon steel with 304 rods but you can not use them on 316 stainless. I hope I got that right, it has been many years...
Regards, Mrx99

[lhazleton]

[QUOTE=NightOfDarkness;28596]I believe you could tell the difference after you run your cell if its 316L your water will stay clean/clear anything less will turn your water brown. Youll know after you run your cell for few hours

Not to be argumentative, but I've been using nothing but 304 with a 28%KOH e/lyte for quite a while now. My solution stays clear & I haven't noticed any deterioration of my plates. I run a minimum of 6 bi-polar plates per stack, so I imagine this helps.