ΔE effect and magnetomechanical coupling factor in Fe80B20and Fe78Si10B12glassy ribbons

Field annealing experiments on amorphous Fe
80
B
20
ribbon (Metglas 2605) and amorphous Fe
78
Si
10
B
12
ribbon (Tsuya, Tohoku University) are reported. The maximum magnetomechanical coupling constant,
k
, and change in Young's modulus, ΔE/E
0
found in Fe
80
B
20
were 0.64 and 0.87, respectively, for an anneal of 376° for 6 min in a field of 2.0T. The maximum
k
for Fe
78
Si
10
B
12
was found to be 0.82, following a similar anneal at 373°C. This is higher than 0.75 reported by Tsuya and Arai for Fe
78
Si
10
B
12
, previously the highest known for any material.