etchant 1

[traytown]

Hi All ,

Would anyone happen to know the best etchant to use on cmsx4 supralloy for optical microscopy, i seem to be getting a slight over etch and pooling around the
edge of the sample using general nimomic etchant?

 

[TVP]

Standard etchant for nickel-based superalloys is glyceregia: 15 mL HCl, 10 mL glycerol, 5 mL HNO3. Swab specimen for 5-60 seconds. Mix fresh. Do not store. Use under a hood. Modified glyceregia is 60 mL glycerol, 50 mL HCl, 10 mL HNO3. This version reveals precipitates better. Use under hood; do not store. Add HNO3 last. Discard when dark yellow. Immerse or swab specimen 10-60 seconds.