J. Moya et al., STRUCTURAL, MECHANICAL AND MAGNETIC-PROPERTIES IN HEAT-TREATED -LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-12) ALLOY RIBBONS, Nanostructured materials, 8(5), 1997, pp. 611-621
The evolution of structural (X-ray, Mossbauer spectroscopy), mechanica
l (Young's modulus, Delta E effect) and magnetic (hysteresis loops) pr
operties of Fe73.5Si22.5-x BxNb3Cu1 (6 less than or equal to x less th
an or equal to 12) alloy ribbons is followed after heating at increasi
ng temperatures, T-a, up to full devitrification of the amorphous prec
ursors into a nanocrystalline state. Overall modifications in structur
e correlate with magnetic and mechanical characteristics, which are an
alyzed through the induced changes in parameters as internal stress an
d magnetostriction. Relaxation of amorphous structure (T-a approximate
to 440 degrees C) results in magnetic softening and increase of Delta
E effect. First stages of crystallization (T-a approximate to 480 deg
rees C), including a Cu clustering, induces a relative magnetic harden
ing and reduction of Delta E effect. Optimum nanocrystalline state (T-
a 540 degrees C) with the softest magnetic behavior leads to a final i
ncrease of Young's modulus. The influence of relative weights of Si an
d B is also analyzed. (C) 1997 Acta Metallurgica Inc.