Magnetic properties and crystallization behaviour of Fe28.75Co28.75Ni17.5X8B17 (X=Si, Ge) metallic glasses

The development of Fe- and Co-based amorphous soft magnetic materials with low critical cooling rate for glass formation has become an important topic both for fundamental and technological reasons. We have synthesized new alloys with composition Fe28.75Co28.75Ni17.5X8B17 (X=Si or Ge) and we have studied the evolution of their magnetic and crystallographic properties when heated from room temperature to 900 deg. C. The techniques used to measure their evolution are in situ powder neutron diffraction and Faraday magnetic torque. We observe a phase stability competition between the SC (α2), BCC (α) or CCP (γ) forms