Jump to content

Recommended Posts

Posted (edited)

While moving the copious quantities of stuff from the old back yard to the new back yard, I came upon 6 pieces of stainless steel flat bar. They are 4" w by .250" thick and about 6 feet long. I don't know where they came from or what type of stainless they are. However, they do have some markings on the side.

HT#4FC4 and ASTM A240. Now I know that ASTM A240 is a standard for manufacture of chromium and nickel stainless steels, but who knows what kind? It doesn't "feel" or look like 400 series. Could it be 300 series?

 

Stainless flats.jpg

Edited by Joshua States

Share this post


Link to post
Share on other sites

Just knowing A240 isn't enough (and the manufacturer's heat number doesn't help if you don't know the manufacturer).  There should be more markings on it, otherwise you are going to have to guess (or do some testing).  

Share this post


Link to post
Share on other sites
On 5/29/2018 at 11:22 AM, Jerrod Miller said:

Just knowing A240 isn't enough (and the manufacturer's heat number doesn't help if you don't know the manufacturer).  There should be more markings on it, otherwise you are going to have to guess (or do some testing).  

The only other markings are the dimensions, and the length seems to be quite a bit shorter than the 145 shown.......so any other identifiers have been cut off.

It is non-magnetic, so that would apparently rule out 400 series. What other tests can you suggest to determine the general family/series?

Share this post


Link to post
Share on other sites

My google fu shows a lot of 300 series results; one result said A240 should be ferromagnetic in annealed condition.

Share this post


Link to post
Share on other sites
Posted (edited)
3 hours ago, Joshua States said:

What other tests can you suggest to determine the general family/series?

Sending to a lab for analysis (not a great suggestion, I know).  Personally, I would just play the odds.  It is most likely 304, 304L, 316, or 316L, in that order.  In terms of what you could use it for, it doesn't really make a difference which one it is.  

OK, so personally I would test it, but I have access to a spectrometer.  But if I didn't, I'd play the odds.  

Edited by Jerrod Miller
Added a note for clarity.
  • Thanks 1

Share this post


Link to post
Share on other sites

Thanks Jerrod. Any of those would be fine for my purposes. I'm going to cut a hunk off of one of the bars and see how it polishes.

Share this post


Link to post
Share on other sites

I'd bet money or Jerrod's approach.  304 and 316 are so common, it just about has to be one of those.  Unless chemical resistance is a big issue for your use, you probably wouldn't see the difference.

304 does not stand up to salt water or salt spray nearly as well as 316, so if you spray some salt water on it and it starts to rust, it is likely 304.  (Look up 304 vs 316 in architectural applications to see some comparison photos)

304 is tough to drill, but 316 seems worse to me.  One revolution of the drill without removing a chip is enough to work harden either.  If it eats your drills for lunch and spits in your face it is 304.  It it actually takes the drill out of the chuck and shoves it up your...   ...well, then it is 316.

  • Haha 1

Share this post


Link to post
Share on other sites
On ‎6‎/‎5‎/‎2018 at 9:39 AM, Brian Dougherty said:

304 does not stand up to salt water or salt spray nearly as well as 316,

Hmmm....so I guess making salt pot tools (tongs and hooks) is not advisable.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×