A. Inoue et al., PREPARATION OF AMORPHOUS FE-SI-B AND CO-SI-B ALLOY WIRES BY A MELT EXTRACTION METHOD AND THEIR MECHANICAL AND MAGNETIC-PROPERTIES, Materials transactions, JIM, 36(7), 1995, pp. 802-809
Amorphous (Fe, Co)-Si-B ternary and quaternary wires were found to be
produced over a wire diameter range of 20 to 80 mu m by a melt extract
ion method using a copper wheel with an edge angle of 60 degrees. The
wires without any concaves in the transverse cross section were prepar
ed in the extraction condition where the circumferential velocity of t
he wheel and the rising velocity of the molten alloy are in the range
of 20 to 40 m/s and 0.1 to 4.0 mm/s, respectively. The resulting amorp
hous wires have good bending ductility in the wire diameter range belo
w 80 mu m for the Fe75Si10B15 alloy and below 60 mu m for the Co72.5Si
12.5B15 alloy. The thermal stability and mechanical properties except
tensile fracture strength (sigma(f)) for theamorphous wires are nearly
the same as those for the melt-spun amorphous ribbons. The sigma(f) i
s 3800 MPa for the Fe75Si10B15 wire and 3600 MPa for the Co72.5Si12.5B
15 wire, being about 10% higher than those for the corresponding ribbo
n samples because of the low degree of stress concentration resulting
from the good smoothness on the outer surface. The magnetic properties
of saturation magnetization, coercivity and effective permeability at
1 kHz for the wires are nearly the same as those for the ribbons. The
squareness of the hysteresis B-H loop for the Fe-Si-B amorphous wire
is better than that for the same Fe-based ribbon and the sharp output
voltage due to the reversion of magnetic flux is also observed for the
present Fe78Si10B12 amorphous wire. The combined properties of good m
echanical properties and unique magnetic properties leading to the gen
eration of the sharp output voltage seem to be promising for the subse
quent development of the present fine amorphous wires.