The effect of grain boundary microstructure on Barkhausen noise in ferromagnetic materials

The Barkhausen noise (BHN) was measured in ferromagnetic materials to inves tigate the interaction between the grain boundary microstructure and magnet ic domain walls. The grain-size effect of the BHN was studied for pure iron specimens. The Hall-Petch type relationship between the.-rain-size and the BHN power was found. The effect of the grain-boundary misorientation on th e BHN was also studied for silicon steel specimens. The BHN power increased with increasing the grain boundary misorientation angle. It has been sugge sted that the arrangement of magnetic domains along a grain boundary can be affected by the grain boundary character and that hysteresis of magnetizat ion can be optimized by controlling the grain boundary microstructure in fe rromagnetic materials. The importance of understanding the behavior of magn etic domains was discussed in terms of the control of magnetic properties i n ferromagnetic materials. (C) 2001 Published by Elsevier Science Ltd on be half of Acta Materialia Inc.