B-H hysteresis loop

The operating state of a permanent magnet lies in the second quadrant of a B-H hysteresis loop since the magnet is always subject to its own demagnetizing field. Apart from its coercivity and remanence, a permanent magnet material is rated by its maximum energy product ... 

Figure 12.15 The complete B H (hysteresis) loop of a ferromagnetic sohd...

Mamiya H, Jeyadevan B. Magnetic hysteresis loop in a superparamagnehc state. IEEE Transactions on Magnetics. 2014 50 4001604. DOI 10.1109/TMAG. 2013.2274072. 

Fig. 7.2 M-H hysteresis loops of the samples shown in Fig. 7.1(a) Co-Ni-Fe-P soft magnetic underlayer electroless-deposited, (a) without and (b) with an external applied magnetic field [15]. 2004 IEEE...

Fig. 7.9 M-H hysteresis loops of SmCOj thin films with perpendicular magnetic anisotropy, (a) Sample A, (b) sample B, and (c) sample C correspond to those in Table 7.1. Thick and thin lines represent the loops measured in the directions perpendicular and parallel to the film plane, respectively [45]...

Concept Check 20.6 It is possible, by various means (e.g., alteration of microstructure and impurity additions), to control the ease with which domain walls move as the magnetic field is changed for ferromagnetic and ferrimagnetic materials. Sketch a schematic B-versus-H hysteresis loop for a ferromagnetic material, and superimpose on this plot the loop alterations that would occur if domain boundary movement were hindered. 

Figure 3.26(a) and (h) gives results for nitrogen on a compact of silica. Curve (a) is a comparison plot in which the adsorption on the compact (ordinates) is plotted against that on the uncompacted powder (abscissae) there is a clear break followed by an increased slope, denoting enhanced adsorption on the compact, at p/p° = 0-15, far below the lower closure point ( 0-42) of the hysteresis loop in the isotherm (curve (b)). A second compact, prepared at 64 ton in" rather than 130 ton in", showed a break, not quite so sharp, at p/p° = 0-35. 

Fig. 1. Magaetic hysteresis loop of an initially demagnetized material (curve 1) where poiat A corresponds to (BH), and the slopes of lines B and C, with tangents to curves 1 and 2, represent = B /H and respectively. Terms are defined ia the text.

For perm anen t-m agnet materials where the coercivity is large, the demagaetizatioa curve, which correspoads to the secoad quadrant of the hysteresis loop, sometimes is plotted as the polarization J(= B — vs H(B — H vs H) to show the intrinsic characteristics of the material. The value of... 

Figure 11. Grazing incidence X-ray diffraction patterns (a) and OD spectra (b) of the as-implanted Au-Fe sample and of the sample after annealing at 600 °C for 1 h in reducing atmosphere, (c) Hysteresis loops of the as implanted Au-Fe and of the only-Fe samples measured at 3 K.

Fig. 7.8. The full unfolding of the stationary-state locus (a) corresponding to a winged cusp singularity, (b) unique (c) isola (d) mushroom (e) single hysteresis loop (f) hysteresis loop + isola (g) reverse hysteresis loop (h) reverse hysteresis loop + isola.

Because of hysteresis, energy is dissipated as heat in a magnetic material as it is taken round a complete B-H loop, and the hysteresis energy loss Wh per unit volume of material is... 

Figure 17. (A) Typical hysteresis loop of a FePt-Fe3Pt nanocomposites and (B) Second-quadrant B-H curves for the annealed 4 nm Fe58Pt42 nanoparticle assembly and hard-soft exchange-coupled FePt-Fe3Pt nanocomposite [75].

Fig. 9.3 Hysteresis loops for various values of separation d of hexagonal dots array (a) net M-H loops with net demagnetizing field, (b) the M-H loops in average of individual dot [27], 2002 IEEE...

In Table 2 the pore volumes are given for the samples (a) Cd-X prior to sulfidation, (b) after sulfidation without prior dehydration and (c) after subsequent calcination of sample b at 623 K for 24 h in an Ar-flow. The adsorbed amount aj corresponds to the relative pressure p/po 0.32, i.e. to the junction of both branches of the hysteresis loop. The value of... 

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