A SCALING LAW FOR NONDESTRUCTIVE EVALUATION OF SHOT PEENING INDUCED SURFACE MATERIAL PROPERTY DEVIATIONS

Shot peening is frequently used to improve mechanical characteristics of metallic components’ surfaces. The physical properties of shot peened surfaces exhibit deviations from their bulk values. This paper shows that there exists a scaling law (universality) among seemingly unrelated material property deviations and among different peening conditions. We present examples and support for scaling behaviors based on experimental data on Almen strip deflection, cold work and residual stress profiles of a shot peened nickel‐base superalloy (Waspaloy), and swept frequency eddy current signals used for NDE studies of another shot peened nickel‐base superalloy (Inconel 718). In addition, a fast impedance calculation formula for a coil placed on a metal with small, continuous conductivity deviation is presented and used for analytical and numerical study of eddy current signals.