* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download estimation of subsurface residual stress depth profiles via wideband
Survey
Document related concepts
Neutron magnetic moment wikipedia , lookup
Work hardening wikipedia , lookup
Giant magnetoresistance wikipedia , lookup
Scanning SQUID microscope wikipedia , lookup
Viscoplasticity wikipedia , lookup
Low-energy electron diffraction wikipedia , lookup
Superconductivity wikipedia , lookup
Nanochemistry wikipedia , lookup
Strengthening mechanisms of materials wikipedia , lookup
Tunable metamaterial wikipedia , lookup
Magnetic skyrmion wikipedia , lookup
Multiferroics wikipedia , lookup
Cauchy stress tensor wikipedia , lookup
Stress (mechanics) wikipedia , lookup
Viscoelasticity wikipedia , lookup
Ferromagnetism wikipedia , lookup
Transcript
Estimation Of Subsurface Residual Stress Depth Profiles Via Wideband Magnetic Barkhausen Noise Analysis And Correlative Stress Modeling James Thomas, et al. American Stress Technologies, Inc., USA Abstract Surface residual stresses in ferromagnetic materials can be evaluated non-destructively with Magnetic Barkhausen noise (MBN). Residual stresses directly affect the magnetostrictive energy of a sample, thus altering the way that magnetic domain walls move; this results in a quantifiable change in the MBN emitted by the sample in the presence of an externally applied alternating magnetic field. The effective depth of emission of MBN for traditionally used frequency bands is very near the surface, hence the correlation between MBN properties and surface residual stresses. By analyzing a wider range of frequencies the effective maximum depth of emission of a MBN signal can be estimated. As a result, an approximate MBN-Depth relationship can be drawn. Approximate MBN-Depth relationships are calculated and compared to residual stress depth profiles in this study. Residual stress depth profiles are measured using X-Ray diffraction and electrochemical layer removal. This report introduces a correlation-based model for estimation of residual stress profiles. This method is tested for efficacy with several sample sets, including ground bearing rings, which yield accurate results within a limited range of depths. Stress modeling via MBN is demonstrated to be an effective method for non-destructive approximation of subsurface residual stresses. Keywords: