Using an eddy current method with inverse analysis to determine the thickness of the layer modified by cavitation peening at the surface of type 316 L austenitic stainless steel

The depth to which a material is modified by cavitation peening affects the stress corrosion cracking resistance and fatigue properties of the material. Thus, determining the thickness of this modified layer is important for evaluating the peening intensity. In this paper, a nondestructive eddy current method was used to accomplish this. The material under test was stainless steel, AISI 316 L and the thickness of the modified layer, which had a simple stress distribution, was determined by inverse analysis using a surface response methodology. The results demonstrate that the thickness of the layer can be determined by the eddy current method combined with inverse analysis using a response surface methodology.