Magnetic Hysteresis Loop Simulation
Magnetise a ferromagnet, remove the field, and it stays partly magnetised — that lag is hysteresis. This simulation traces the B–H loop as you cycle the applied field, and shows the domain structure behind each part of the curve.
How to use this simulation
- Cycle the applied field strength H up and down
- Choose between soft and hard magnetic materials
- Watch the domain alignment alongside the curve
What to look for
- The return path never retraces the outward path — that gap is the hysteresis
- Remanence and coercivity are read directly off the axes intercepts
- Hard materials enclose a much larger area, so they waste more energy per cycle but make better permanent magnets
The physics behind it
As H increases, magnetic domains align and B rises steeply until saturation. Reducing H to zero leaves a remanent flux density B_r, because domains do not fully relax. Reversing H to the coercive field H_c is needed to bring B back to zero. The loop's enclosed area equals the energy dissipated as heat per cycle, which is why transformer cores use narrow-loop soft magnetic materials.