Powder Technology, Vol.264, 541-543, 2014
Ferromagnetic granular exchange interactions of nickel and iron
Micromagnetic grains of nickel and iron were blended to investigate whether the magnetic exchange interaction was significant to produce a bulk result in a measured deflection by a fixed applied magnetic field. The results follow the same trend as Slater-Pauling's magnetization density calculations for nickel iron films, most notably a stronger following with a finer grain. Furthermore, by adding chromium into nickel and iron blends, the Invar minimum shifts toward less iron in nickel. Hysteresis was determined for the same samples through a homemade vibrating sample magnetometer (VSM). Areas of each loop are determined that show a minimum around the Invar transition, followed by sharp increases based on concentration of iron in nickel. These results help further understand the extent of magnetic exchange interactions in granular materials. (C) 2014 Elsevier B.V. All rights reserved.