Inconel 738C microetchant and technical data 1

[vpg]

Does anyone have an idea what etachts to use for metallographic examination of cast Inconel 738C ?
I find the data on Inconel 738C is very scarce. I tried a mixed solution of 10 ml nitric acid, 10 ml acetic acid, 15 ml hydrochloric acid and 2-5 drops glycerin, but was not able to get satisfactory results.

Also any information source regarding this material would be greatly appreciated.

Thanks.

 

[metengr]

I would try the following etchants;

Marble's Reagent (used on nickel base and superalloys)
10 grams of copper sulfate
50 ml of HCl
50 ml of water (DI)
if necessary add a few drops of sulfuric acid.

OR
Kallings #2

5 grams of copper chloride
100 ml of HCl
100 ml of ethanol

If this does not work, contact Buehler Ltd., in Lake Bluff, IL. Mr. GF Vander Voort could probably recommend a microetchant for this alloy.