Methods of test of the magnetic properties of permanent magnetic (magnetically hard) materials
1 Subject content and application scope
This standard specifies the methods of test of the magnetic properties of permanent magnetic (magnetically hard) materials
This standard is applicable to alnico permanent magnetic, ferrite permanent magnetic, rare earth permanent magnetic and other permanent magnetic materials.
2 Normative References
GB2900.4 Electrotechnical terminology - Special alloys for electrical equipment
3 Terms
3.1
demagnetization curve
second or fourth quadrant of the saturated hysteresis loop this part is defined by remanence and coercivity HCB or intrinsic coercivity HCJ (see Figure 1)
3.2
Maximum BH product
maximum value of the product of magnetic flux density (magnetic induction intensity) and corresponding magnetic field intensity on the demagnetization curve, with the coordinates of (BH)max point expressed by (Bd,Hd) (see Figure 1)
3.3
recoil line, recoil permeability
recoil line of permanent magnetic material refers to partial hysteresis loop of a point on the demagnetization curve at recoil state, recoil permeability refers to the ratio of the average slope of recoil line to the magnetic constant (see Figure 1)
1 Subject content and application scope
2 Normative References
3 Terms
4 System of units
5 Measurement of permanent magnetic materials whose intrinsic coercivity HCJ is less than or equal to 600kA/m
6. Measurement of permanent magnetic materials with intrinsic coercivity HCJ greater than 600kA/m
Annex A (Supplementary) SI units related to magnetic quantity
Annex B (Supplementary) Minimum saturation magnetization field intensity of some permanent magnetic materials
Annex C (Supplementary) Influence of air gap on measurement error
