Remanent coercive force

Energetic analysis shows the dependence of using magnetie materials from relation of coercive force on magnetization to remanent induction. The permanent magnets... 

As the appHed field is reduced, the iaductioa does aot retrace curve 1 but foUows curve 2 as the domaias at first merely rotate back to the aearest local easy axis directioa. The value of B at i/ = 0 is the remanent iaductioa. At H = which is the coercive-field strength of coercive force or... 

Hysteresis curves for a magnetically hard and a magnetically soft ferromagnetic material. S = saturation magnetization, R = remanent magnetization, K = coercive force... 

Strength H r is needed to remove the remanence. He, the magnetic field at which Js becomes zero, is called coercive force or coercivity. Each type of magnetism shown in Figure 6.8 is associated with characteristic features which are displayed by the different Fe oxides. 

Substances used as permanent magnets need a large coercive force, so that they are not easily demagnetised and preferably should also have a large remanent magnetisation. These substances have fat hysteresis curves. They are often made from... 

If the field is removed, there is a residual magnetization or remanence, Br. A reverse field, //, (coercive force), is required to demagnetize the material. The area enclosed by the B-H curve (hysteresis) is the energy loss per cycle, and the... 

For permanent magnets, materials with the highest possible remanence and coercive force are required, so that they cannot be easily demagnetized by external magnetic fields. 

The coercive force /hc and remanence /r achievable in the storage medium are important properties ... 

Uyeda S (1957) Thermo-remanent magnetism and coercive force of the ilmenite-hematite series. J Geomag Geoelectrtr 9 61-78... 

Fig. 9. Comparison of B versus H plots and J versus H plots. In the SI system B and J are in Tesla, H in A/m. The remanence is indicated by B and JT. The corresponding coercive forces are represented by...

The effect of a variable Nd and B concentration was extensively investigated by Sagawa et al. (1984a). They found that the remanence Br shows a comparatively small concentration dependence. By contrast, the intrinsic coercive force jHc depends strongly on the Fe concentration. The marked decrease of the maximum energy product ( BZf)max observed for high Fe concentrations is mainly due to the rapid decrease of jHc in this concentration range. This behaviour may be under-... 

New permanent magnet materials, such as samarium-cobalt and, a fortiori, neodymium-iron-boron alloys, are also of special interest in the design of static devices with specific magnetic-field configurations. Apart from high remanence and coercive force values of magnets made of these materials, Chavanne et al. (1987) emphasize the presence of large anisotropy fields in the conception of these devices. 

Figure 1 Magnetization curve. Mr, remanence magnetization He, coercive force.

Alnico /al-ma-koh/ (Trademark) Any of a group of very hard brittle alloys used to make powerful permanent magnets. They contain nickel, aluminum, cobalt, and copper in various proportions. Iron, titanium, and niobium can also be present. They have a high remanence and coercive force. 

Magnet type Remanence (mT) Depending on the variety Intrinsic coercive force, Hci (kA/m) Depending on the variety Maximum operating temperature (°C) Depending on the variety... 

Magnet Remanence, Bj Intrinsic coercive force. Maximum operating... 

Name Al Composition, Weight Percent Ni Co Cu Other Remanence, Br,G Coercive Force, H, 0 Maximum Energy Product, (BEf)max. G-O XlO" ... 

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