Magnetic Hysteresis (B-H Curve Properties) (B-H curve: retentivity, coercivity, hysteresis loss)
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B-H curve: retentivity, coercivity, hysteresis loss
What each symbol means
| Symbol | What it stands for |
|---|---|
| B | Magnetic flux density (T) |
| H | Magnetizing field intensity (A/m) |
| B_r | Retentivity — B when H = 0 (residual magnetism) |
| H_c | Coercivity — H needed to make B = 0 |
When to use this
Ferromagnetic materials only. Area of B-H loop = energy loss per cycle per unit volume. Soft iron: narrow loop (transformers, electromagnets). Steel: wide loop (permanent magnets). Hysteresis loss ∝ frequency × loop area.