I got a high asymmetry in magnetic hysteresis loop of NdFeB magnet even though there is no particle rotation in VSM. Can anyone tell me the possible reason for it?
I have come across a similar problem a few years ago. It could be the limitation of the measurement equipment. Let me explain... Probably your measurement equipment cannot supply enough high field to fully magnetize the magnet i.e., you are not on a "true" major loop. Asymmetry will go away if you apply a sufficiently large field.
You can get a shift of the hysteresis loop, when the sample has a remanence. The first thing I would try is to demagnetize it. As the coercivity is very high, you could try heating it to the curie temperature and cooling it in a zero field environment. Then remeasure the hysteresis loop.
I have seen the asymmetric M(H) loops in Ni-Mn-In Heusler alloy. This is because of first order phase transitions and therefore existence of thermal hysteresis in these materials.
- Badges
- Science topic