Effect of Gd and Fe doping on magnetic properties of Al87Y5Ni8 amorphous alloy

In this paper we present and discuss magnetic properties of the Al87Y5Ni8, Al87Y4Gd1Ni8, Al87Gd5Ni8, Al87Y4Gd1Ni4Fe4 and Al87Gd5Ni4Fe4 amorphous alloys. The examinations have been concentrated on a possible magnetic ordering at low temperatures and its modification by amorphous surroundings as well as different magnetic moment of alloying additions. It was shown that magnetic properties of the Al87Y5Ni8 amorphous base alloy correspond to a superparamagnetic body with Ni magnetic clusters. Magnetic moment of Ni atom in amorphous aluminum matrix is found to be 0.3 μB that corresponds to less than 50 Ni atoms per one cluster. Gd doping of the base alloy leads to a decrease of the resultant magnetic moment of Ni clusters that can be explained by some antiferromagnetic coupling Ni-Gd and Ni-Ni within magnetic clusters.