Calibration and Validation of Micromagnetic Data for Non-Destructive Analysis of Near-Surface Properties after Hard Turning

Abstract Micromagnetic non-destructive (NDT) methods offer a great potential for the analysis of near-surface properties after machining due to potential time and cost reduction as well as the option to be implemented into the machining process. As a result, the development of soft sensor concepts including micromagnetic NDT methods is in focus of current investigations in order to eventually improve the surface integrity of machined components and, thus, service life and reliability. However, a preceding calibration based on empirical data as well as a reliable validation is often referred to as one of the main challenges of micromagnetic NDT methods. The present study provides insights into the calibration and validation of a micromagnetic 3MA-II system for NDT analysis of the near-surface properties, with a focus on the residual stress depth profiles after hard turning of 51CrV4 specimens. Different calibration functions as well as a combination of different NDT methods are taken into consideration. The results and the potential of the 3MA system as well as open challenges are critically discussed.