Classification of magnetic magnetic materials

 Classification   of magnetic  materials.     The  magnetic  properties  of  the materials  are  characterised  by their    relative  permeabilities In accordance with  the  value  of relative  permeability  the materials may be  classified  in the following  three ways : 

1. Ferromagnetic  materials.  

The relative  permeability of these  materials are much   greater than unity and dependent on the field  strength  . The principal  ferromagnetic  elements  are iron  cobalt  and nickel  

2 para magnetic  materials.  The relative  permeability  of these  materials  are slightly  greater  than  unity and are slightly  magnetized  Aluminum  platinum and oxygen  belongs  to this category  

 

3 Diamagnetic materials  . The relative  permeabilities  of these materials  are slightly  less than uniy  silver  copper  bismuth  and hydrogen  are all Diamagnetic  materials