Villela's reagent
Etchant for stainless and high-chromium steels: 1 g picric acid + 5 mL concentrated HCl + 100 mL ethanol. Targets prior austenite grain boundaries and reveals the strained zone where chromium oxide passivation defeats Fry's.
Etchant for stainless and high-chromium steels: 1 g picric acid + 5 mL concentrated HCl + 100 mL ethanol. Targets prior austenite grain boundaries and reveals the strained zone where chromium oxide passivation defeats Fry's.
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