Call for T23/P23 Micrographs 2

[Guest102023]

I am seeking contributions of micrographs of this material (I hope this is not an inappropriate request for this forum). Any offering should contain relevant information such as:

- material specification & thickness
- hardness
- composition if known
- heat treatment condition, esp. hold time & temp. of PWHT
- weld zone; i.e., CGHAZ, ICHAZ, base metal
- metallographic preparation and magnification

I am having some trouble assessing the microstructures of T23 tubes and welds in the course of several F/A jobs (done for one client only). Also, my self-education on this material has so far been hampered by the questionable metallurgical and fabrication quality of the parts I have examined. I am not fully confident in calling ferrite and GB precipitates (carbides). When you never see a normal structure, it is hard to assess an abnormal one

The quality of metallography I can obtain is excellent, although I am open to advice on alternative etching practice (I have so far used 2% nital). I have googled CSEF steels extensively, but it seems that some time ago research papers stopped including etching details. There are some excellent resources on the net for P91 (e.g., Camridge U), but there is much less available for grade 23.

Thanks in advance!

 

[cloa]

Appropriate forum but maybe you want to serious consider joining a metallographers organisation such as this for a more all-round view of such a detailed area.

http://www.asminternational.org/portal/site/ims/

 

[Guest102023]

The problem with sites like those is precisely that they are 'all-round'. You could stock a website with 100,000 micrographs and still not have the one you are looking for. This forum has a number of people with expert knowledge of these specialty alloys and direct experience in practical situations like fabrication and FFS.

 

[Metaljon]

I have attached a articles on P23 material from Oerlikon. If you follow the references there are other micrographs. We use nital for etching as well.

http://nz.linkedin.com/pub/jonathan-smith/39/25/589

 

[metengr]

Excellent magazine technical reference by Metaljon.

 

[Guest102023]

I have that Oerlikon document, but the quality of the images is poor (at least on my screen).

 

[Metaljon]

Yes the images are a bit grainy. If you are a member of TWI UK they have some excellent membership reports which fully characterise material types and weld structures including the V, W addition alloy steel weldment variants.

http://nz.linkedin.com/pub/jonathan-smith/39/25/589

 

[Guest102023]

This is one of the better resources I have found ...

 

[metengr]

Nothing shows up.

 

[Guest102023]

2nd attempt

 

[Guest102023]

once more ...

 

[Guest102023]

#4

 

[Guest102023]

I give up. This is the paper, maybe you have it:

Fabrication & Weldability of Grade 23 Tubing and Piping, by Poli et al.

Can't find a

http://www link

to direct you to.

 

[Guest102023]

I'll try shortening the filename. The authors are with Air Liquide, who own Oerlikon.

(I have uploaded files here before. Honest.)

 

[TVP]

bs,

Have you tried etching with picral? Often it is helpful to use both nital & picral (combined or separate) in order to reveal different aspects of the microstructure. George Vander Voort has a number of papers & presentations available for free download, although none of them directly discuss T23 (I think). Here is one paper that does a really good job of illustrating the differences:

http://www.georgevandervoort.com/met_papers/IronandSteel/EtchingIsothermallyTreatedSteels.pdf