Abstract
Microstructures of thick Fe80.5Si6.5B12C1 amorphous ribbons which were crystallized by the addition of 0.01 mass%Aluminum have been examined. The ribbons with the thickness of 66-74 μm were cast by using a multiple slotted nozzle in a conventional single roll method. The microstructures of the as-cast ribbons were as follows: The region near the free surface of the ribbon was fully crystallized. The confirmed phases were primarily α-Fe which forms dendritic structures, Fe2B and orthorhombic-Fe3B. The roll side of the ribbons was primarily amorphous with α-Fe. The middle region in the ribbon thickness direction was primarily amorphous with only a trace of α-Fe. In the free side surface, it was found that (110) orientation of the dendritic α-Fe occurred by the addition of Aluminum and it is considered that the α-Fe formed directly from the molten alloy during casting.
