Counting Ferrite/Austenite % in Duplex microstructure

[jrupert24]

I am trying to do a % austenite/ferrite count on a weld crossection of 2205. NACE MR0175 requres the count per ASTM E562. I have the standard, but have never used it before. It seems like it would be really difficult to do in the weld considering the microstructure. Has anyone followed the ASTM standard that could give me some pointers. Is there another acceptable way or some reference material that could be suggested. I ran my ferrite gage across the crossection and get acceptable results, however, I would like to meet the ASTM spec if possible.

 

[TVP]

Here is a good description of the method by George Vander Voort, who likely authored ASTM A 562:

http://www.buehler-asia.com/brochure/apps_support-tech-notes_vol1_issue5.pdf

 

[metengr]

Correction; ASTM E562.
My advice would be to send the sample to a met lab and have them determine the duplex phase constituents.

 

[jrupert24]

thanks for the info.....I saw that ASTM E562 references E 1245 for automatic image analysis. I ended up figuring out how to use the Buehler Omnimet software with the metallograph to do this function.....works great, however, a little subjectivity required....beats the hand count method....