Saturation magnetic induction

To model the transformer, an ideal center-tapped transformer is combined with a nonlinear core model for the F material. As this circuit counts on the saturation of the core, a SPICE primitive inductor will not work. By adding this nonlinear core model across the input of the center-tapped transformer, the magnetizing inductance and saturation characteristics of the core are realized. 

Figure 2 shows the two hysteresis loops for a medium and a head material. The coercivity, FT, the saturation magnetization, M or induction, Bs, remanent magnetization, M or induction, B and the permeability, JJ, differ for the two materials. 

The concept of an anisotropy magnetic field HA, which is referred to simply as the anisotropy field , is also introduced to describe magnetic anisotropy. The anisotropy energy is considered to be that of the saturation magnetization moment Ms in an induction /r0//A, i.e. K= -/r0//AMs cos 9, where 9 is the angle between IIA and Ms. 

COercivity. The magnetic intensity required to reduce the magnetic induction in a substance from saturation to zero. 

Sun NX, Wang SX (2000) Soft high saturation magnetization (Fe, inductive write heads. IEEE Trans Magn 36 2506-2508... 

It must have a high spontaneous magnetization, Ms, in the temperature range of practical interest (typically around room temperature). The saturation intrinsic induction, Bis = AttMs (in gauss) sets the upper limits for the remanent flux density, Br = Bls, and for the energy product, BH)mzx = ( B1%)2 (in MGOe). 

Fig. 8. Room-temperature spontaneous magnetization values ( saturation intrinsic induction ) of transition metal-rich RE-TM(-B) compounds of interest for permanent magnets.

Magnetic field Magnetic induction Magnetization Spontaneous magnetization Saturation magnetization Magnetic flux Magnetic moment Coercive field Remanence... 

Estimate (a) the saturation magnetisation and (b) the magnetic inductance for the cubic ferrite CoFe204 with the inverse spinel stmcture. Co " " is a d ion. The cubic unit cell has a lattice parameter of 0.8443 nm and contains eight formula units. Assume that the orbital angular momentum is completely quenched in this material. 

Figure 1. Typical curve representing the dependence of magnetic induction B on magnetic field H for a ferromagnetic material. When His first applied, B follows curve a as the favorably oriented magnetic domains grow. This curve flattens as saturation is approached. When His then reduced, B follows curve b, but retains a finite value (the remanence B,) M H = 0. In order to demagnetize the material, a negative field -H (where H is called the coercive field or coercivity) must be applied. As H is further decreased and then increased to complete the cycle (curve c), a hysteresis loop is obtained. The area within this loop is a measure of the energy loss per cycle for a unit volume of the material.

Low carbon steels are the most widespread magnetic metallic materials for use in electric motors and inductive components such as transformers, chokes, and a variety of other AC applications which require high magnetic induction at moderate to low losses. This is mainly due to the high intrinsic saturation polarization of the base element Fe, /s = 2.15 T, and to the low cost of mass produced steels. 

Ferrite type Chemical formula Structure type, crystal system, lattice parameters, strukturbericht, Pearson symbol, and space group Magnetic induction saturation (B/T) Curie U (T,rc)... 

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