Magnetomechanical Acoustic Emission for Residual Stress and Prior Strain Determination.
Abstract
This study evaluated magnetomechanical acoustic emission (MAE) in iron, nickel, steels and an iron-nickel alloy. The intensity of MAE increased with an increasing level of magnetization at 60 Hz and was also dependent on chemical composition, microstructure, applied stress, and prior cold work. Nickel was the highest emitter and the iron-31% nickel alloy was the lowest. Martensitic transformation and cold-working reduced MAE. Applied stress also suppressed MAE, although some enhancements were observed in nickel and A533B steel. A model based on displacement step generation is proposed. The displacement is a consequence of domain boundary motion that alters magnetostrictive strain. The model satisfactorily explains a variety of experimental observations at least qualitatively. However, independent experiments will be needed to confirm some of the assumptions. Results presented amply demonstrate that MAE provides the basis for a new class of nondestructive testing of residual stress and other material parameters of practical interest. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1979
- Accession Number
- ADA081912
Entities
People
- Kanju Ono
- M. Shibata
Organizations
- University of California, Los Angeles