Application of Potentiostatic Etching for Nondestructive Testing of Accumulated Plastic Strain in Austenitic Stainless Steels
Materials Evaluation, 2017, 75(11): 1399-1405.
Recently, demand for a nondestructive technique to detect and evaluate plastic strain and/or cyclic strain damage with high accuracy has increased. A potentiostatic etching technique for the detection and evaluation of plastic strain in austenitic stainless steels was developed in a previous study. Using this technique, many etched deformation twins would appear on a specimen that was pre strained at room temperature and many etched slip lines would appear on a specimen that was pre-strained at a higher temperature, and plastic strain could be evaluated based on the density of these etched lines. In the present study, the applicability of the potentiostatic etching technique to determine the accumulated plastic strain by cyclic pre -straining was investigated. The results indicate that the potentiostatic etching technique is applicable for the evaluation of low-cycle fatigue in the very early stages of fatigue life.
austenitic stainless steel; electrochemical etching; deformation twin; slip lines