Primary precipitation phase with β-Mn structure in FeSiBP base multicomponent metallic glasses

Rapidly quenched amorphous soft magnetic FeSiPB alloys were studied at the initial stages of devitrification by means of transmission electron microscopy and X-ray diffraction. Metastable π-phase with the β-Mn type structure is formed as a primary phase in alloys with 8-9 at.%B, 7-10%Si, 3-5%P. Transition from amorphous to π-phase proceeds via nearly polymorphous transformation, composition of the phase is close to that of amorphous matrix, it contains metalloid atoms at interstitial positions. Small alloying additions are prone to change the type of the primary phase to α-Mn type and related structures.