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Need microetchant procedure

I have an alloy which has an composition FE-%34 NI-3.5CR. I used NITAL (%5-%10)and also %45H20+%45H202+%5 HF etc.I also used PICRAL but I couldn't see any microstructure of. Can you recommend a good etchant for this alloy?

EMRE GULER
research assistant - KIRIKKALE, TURKEY
2003

Good afternoon: I'm not familiar with this particular alloy, and you didn't mention whether it was a cast or wrought alloy, what microconstituents you were looking for, etc. But if you have access to ASM Handbook, Volume 9, Metallography and Microstructures, you can probably find a good etchant. This handbook has separate sections for cast and wrought heat resistant alloys, as well as etchant recipes.

Steve Bizub
- St Louis, Missouri
2004

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This alloy will likely be austenitic (FCC crystal structure), which means that nital and picral will not be suitable etchants. Since I am still on vacation, I do not have access to all of my references, but you may want to try Glyceregia as an etchant. It is 3 parts HCl, 2 parts glycerol, and 1 part nitric acid. Also, try posting this question at http://www.metallography.com, which has an "Ask the Experts" forum similar to this site.

Toby Padfield
Automotive module supplier - Michigan
2004

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2004

Dear Emre,

You can use Vilella's reagent to etch your material.

Vilella's reagent composition 5 ml HCl
1 g picric acid
100 ml methanol [affil links](95%)

M.Özkan
- Turkey