The effect of stress and field annealing on the magnetic properties of amorphous Fe85-xCoxB15

The temperature dependence of the hysteresis loop of ribbons of the composition Fe-85- xCoxB15S (x = 0, 21, 64) and of Co77B23 - in the as cast state as well as after a field and stress annealing procedure - was measured between room temperature and the crystallisation temperature. From the loop the temperature dependence of the coercivity as well as the parameter al (determined from the law of approach to saturation) was obtained and analysed taking the role of quasi dislocations into account. The experimentally determined temperature dependence of the magnetostriction and saturation polarisation was used analysing with a coercivity model. The thus estimated temperature behaviour of the mean anisotropy K agrees with that estimated from disaccommodation experiments.