Etching Hastelloy is difficult due to the anti-corrosive nature of these alloys. Hastelloy’s are high temperature corrosion resistant superalloys that are primarily nickel alloys containing various amount of molybdenum, chromium, colbalt, iron, copper, manganese, titanium, zirconium, aluminum, carobon and tungsten.

Sample Preparation: Hastelloy’s must be properly prepared to reveal the true metallographic microstructure. A number of recommended procedures can be found at the following links:

CAUTION: Safety is very important when etching. Be sure to wear the appropriate protective clothing and observe all WARNINGS on chemical manufacturersSDS (Safety Data Sheets). Also review COMMENTS Section for each etchant.


Etchant Conc. Conditions Comments
Adlers 300 Hastelloy Etchant
Ferric chloride
Copper ammonium chloride
Hydrochloric acid
Distilled water
45 grans
9 grams
150 ml
75 ml
Immerse for several seconds. A very effective etchant for 300 series, austenitic, duplex stainless steels