In th is work, permeabi lity variation of Ni and
Ni-Zn ferrites due to microstracture is slud id. The
conventional wet ceramic techniqe was used for the
preparation of the sampla. The samples were shaped in the
form of toroids and disks and were sintered in differant
tempraturees. using a LCR-meter, inductance of loroid'i was
macsured and tben pennaebility was calculated. To see the
relation between grain sise and permaebility. a series of
SEM photographs were obtained. The results of these
photographs shows that with increasing the si ntering
temperature the mean size of grans will increase. In the
o ther hand, the magnetic measu rement on toroid samples
show that with increasing the mean size of grain the
magnetic premeability increases, bUI Ihis procedure will nOI
continue and then it falls. The reason of this behavior is
describe based on displacing of grain boundaries so that the
porosities faU in the grains