THE PREPARATION AND MAGNETIC-PROPERTIES OF FE-AG GRANULAR SOLID USINGA SOL-GEL METHOD

The Fe-Ag granular metal solid samples with 10% and 30% weight iron ha ve been successfully fabricated using a set-gel method, which are char acterized by X-ray diffraction and transmission electron micrography. The average diameters of iron particles are from about a few nanometre s to a few tens of nanometres controlled by the reducing temperature. The evolution of magnetic properties and microstructure during heat tr eating are described in detail and explained by using the superparamag netism, single domain and multi domain theories. The magnetic anisotro py of the Fe-Ag granular solid is studied by using the law of approach to saturation. It is found that the magnetic an isotropy constant is in the order of 10(5) J m(-3) which is higher than the value of the bu lk iron and increases with the increase of reducing temperature.