Amorphous metallic Fe78Si9B13 fibers, 50 mu m in diameter, produced by
the melt extraction method, have been studied in the as-quenched stat
e and after furnace annealing at 455 degrees C and 480 degrees C for t
imes between 0.5 min and 50 min. Measurements of the M-H loops and fie
ld dependence of Young's modulus have shown that they behave in a way
very like that of amorphous wires. The minimum coercivity of 3 A/m is
greater than that found in wires, and the minimum Young's modulus (sim
ilar to 0.45 times the saturation value) is greater. It is suggested t
hat the core-shell domain model applies in the its-quenched state and
that stress relief followed by surface crystallization dominate the an
isotropy.