Abstract
The potentiostatic etching technique for austenitic stainless steels was studied to observe the variation of the structure by cold-rolling. The etching potentials of each phase (ferrite, austenite and grain boundary) were determined from the etching figures of an annealed AISI 321L stainless steel. 1 N H2SO4 (containing 0.01 g/L NH4SCN) and conc HNO3 solutions were selected as etching solutions. The ferrite phase caused by cold-working was etched at a potential of −0.35 V (vs S.C.E.) in H2SO4, and the distribution of ferrite phase was observed by an electron microscope. The slipping band was etched at −0.2 V, the etching potential of austenite phase. The grain boundary was etched at 1.2 V in conc HNO3, and the deformation of the grain by rolling was observed.
