Abstract
Preparation of the high dense Ni-Zn ferrite were investigated by the hot isostatic pressing. Results obtained were as follows:
The density of specimens after hot isostatic pressing was above 99.8%i but the transverse-rupture strength were decreased to the half value compared to normally sintered ferrite. It was found that lowering of transverse-rupture strength results from fracture of grain boundary which is considered to be due to reduction of grain boundary in hot isostatic pressing.
When the isostatic pressed ferrite was annealed at 1100°C for 3 h in air, the magnetic properties and the hardness of grain boundary clearly recovered up to those of normally sintered ferrite.
