Measurement of the mechanical stress in mild steel by means of rotation of magnetic field strength

doi:10.1016/0308-9126(81)90078-X

NDT International

Volume 14, Issue 5, October 1981, Pages 255-262

https://doi.org/10.1016/0308-9126(81)90078-X Get rights and content

Abstract

Mechanical stress can make mild steel magnetically anisotropic: as a result flux density B and field strength H are not in general parallel to each other. A piece of equipment (the rotation rig) is described that measures the change in direction of H, and results from the rotation rig are given for a bending test (producing compression and tension surfaces) on a mild steel bar. The rotation effect is analysed for two dimensional magnetization and experimental results are given to explain how the different shapes of the B vs H loops, measured in different directions, cause the rotation of field.

References (3)

T.H. Barton et al.
A precision torquemeter based on magnetic stress anisotropy
IEEE Trans Power Apparatus and Systems
(1966)

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Citation Excerpt :
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Measurement of the mechanical stress in mild steel by means of rotation of magnetic field strength

Abstract

A precision torquemeter based on magnetic stress anisotropy

IEEE Trans Power Apparatus and Systems