SATURATION MAGNETOSTRICTION AND ITS ANNEALING BEHAVIOR OF FE100-XBX AND CO100-XBX AMORPHOUS-ALLOYS

Boron content dependences of saturation magnetostriction λs at room temperature in as-quenched and annealed Fe 100-xBx (15≤x≤25) and Co100-xB x (19≤x≤24) amorphous alloys were measured. The value of λs in Fe-B alloys peaks at x=20, while λs in Co-B alloys decreases with increasing boron content. For two series of alloys, nearly quadratic relations between magnetostriction and saturation magnetization σs were found. After 1 hour annealing at 250°C, both λs and σs in Fe-B and Co-B alloys increased. The increase in λs of Fe-B alloys was within 8%, and was larger than that of Co-B alloys. For annealed Fe-B and Co-B alloys, quadratic relations were also observed, which suggests that the increase in magnetostriction arises from the increase in magnetization.