Stabilized SS310S requirements.

[Dawgee]

Hello all,

I've been a reader on the forum for a while but never posted a question.

Today I am in a bit of a doubt and would appreciate some input on the subject.

We had a old project where the project specs required that SS310s should be supplied in stabilized condition and the sub-contractor provided MTC's for this material with Ti and Nb listed in the product analysis. Along with this the plates are Solution Annealed and a min. temp of 1050 Deg C.

Is this sufficient information to understand that the plates were supplied stabilized ?
PS: I am not much into the material parts and want to understand this for my knowledge. Uncle google does not give any clear answers and the new AI is unreliable.

Thank you for your inputs.


DD.

 

[EdStainless]

Frist I'll presume that you are not in the US.
In the US 310S is S31008 and there is no version listed in the specs that has Ti and/or Nb.
So guessing that this is a European alloy.
And the temp listed is an anneal temp (a bit low for this grade but still annealing)
Stabilization should be more like 700C

 

[Dawgee]

Hello Ed,

Thank you for your response, Yes, we are located in the EU.

The strange thing is that when normal plates without stabilization are ordered, the supplier furnishes a MTC without the addition of Ti and Nb and when stabilized plates are ordered, they supply plates with Ti and Nb in them.
So I was beginning to wonder if this is the only way to confirm the product analysis of stabilized plates along with the annealed temperatures.

So to understand what you typed there on the temperatures,

If,
Case 1: Temperature is more than 700deg. C and around the 1000Deg. C. mark, this is above the stabilization temp. and hence not stabilized?

Case 2: If MTC stated annealed temp at 700 deg. C, than the plates are also stabilized?

Sorry, am like Alice in Wonderland into this wonderful chaos.

Thanks,

DD

 

[EdStainless]

If they add Ti and/or Nb then it a stabilized alloy. that is it is capable of stabilization.
If you put it into service at 600C or higher it will naturally happen to form Ti and/or Nb carbides instead of Cr carbides.
If you service is lower than that (450-600C) then you will risk not having the reactions go the way that you want them to.
The distinction here is is a 'stabilized alloy' by chemistry, or has be it been 'stabilize heat treated'.
Very likely you really want both.
So both need to be specified.

 

[Dawgee]

Hello Ed,
Sorry, I did not get a chance to Thank you.

In our case, we have to force stabilize it. So "stabilize heat treated" because the temp. at peak times "may" go above the 600C mark but these are only spikes.

Thanks,

DD