Magnetic hysteresis minor loops in Fe single crystal

Abstract

Magnetic hysteresis minor loops were measured with step by step increase of the magnetic field amplitude, H a , in plastically deformed Fe single crystal. In order to analyse minor loops in connection with the lattice defects, we defined some magnetic parameters, such as the pseudo-coercive force, H * c , and the differential susceptibility under the pseudo-coercive force χ * H . H * c , for instance, is the magnetic field where the magnetization becomes zero in minor loops. In this work, we found the relationship 2H * c = H a to hold over a fairly wide H a range. These parameters are important for representing Bloch wall displacement and the potential energy. The parameters are remarkably sensitive to lattice defects in the field range below the coercive force H c . The relation of 1/χ * H and H * c shows better sensitivity-90 times higher than that for H cfor revealing information on dislocations. In the minor loop measurement, for getting full information on dislocations it is sufficient to have H a = 400 A m −1 .

In situ magnetic measurements under neutron radiation in Fe metal and low carbon steel

“…[9][10][11][12] Minor-loop coefficients deduced from simple relations between parameters of minor loops are independent of the magnetic field amplitude and are much more sensitive to dislocations and grain boundaries than the traditional magnetic properties of the major loop. [9][10][11][12] Minor-loop coefficients deduced from simple relations between parameters of minor loops are independent of the magnetic field amplitude and are much more sensitive to dislocations and grain boundaries than the traditional magnetic properties of the major loop.…”

Magnetic Adaptive Testing of Non-magnetic Properties of Ferromagnetic Materials

“…It was successfully applied for the detection of ferromagnetic phase induced in austenitic steel by plastic deformation [8], and it showed rather promising indications in quality check-up of cast iron [9]. A method very similar to MAT, also based on investigation of the minor loop families, was used for description of the dislocation-density variation in pure iron after plastic deformation [10], and the same authors currently investigate efficiency of the method for testing radiation embrittlement of steel samples [11].…”

Non-destructive indication of plastic deformation of cold-rolled stainless steel by magnetic adaptive testing

“…An interesting approach towards such an attitude was described in Ref. [5], where strain values of plastic deformation of single crystal iron were indicated via slopes of the amplitude dependencies of magnetic pseudo-parameters within families of minor loops. The slopes were found to vary according to the plastic strain magnitudes.…”