DIAGNOSTICS OF AMORPHOUS ALLOY MAGNETIC PROPERTIES AFTER THERMOMAGNETIC PROCESSING

Abstract

Hysteresis magnetic properties formation and plasticity of Fe&Co-based amorphous alloy tapes (brand 30KCP, the Fe–Co–Si–B system) for improvement increase in its properties and ensuring its competitive application on the control basis have been investigated. In researches magnetomeasuring installation have been used. It is intended for automatic magnetic characteristics measurement of soft magnetic materials ring samples by GOST 8.377 techniques. Defined degree of a flexural tension relaxation when annealing tapes. It was established that even at five-minute annealing at a temperature of 360 °C processes of a relaxation manage to take place almost completely. Further change in time of parameter of a relaxation is insignificant. The received dependences of magnetic characteristics on time of thermomagnetic processing at the enclosed field of 10 A/m and their comparison with usual annealing showed that coercive force changes on the same types of curves with insignificant deviations. After thermomagnetic processing in the enclosed field of 21 A/m coercive force in big fields increased approximately by 30 %, in small Hc failure observed around 5 … 15 min of processing as well as Br values increased. This observed result is very interesting in terms of magnetic reversal processes. The lack of stabilization mobile 180° domains borders, at simultaneous course stabilization 90° borders, is reflected in the form of recession of residual induction and growth of magnetic permeability. It is shown that thermomagnetic processing of amorphous alloy of brand 30KCP in not sating longitudinal field with small times of endurance 5…15 min at 360 °C leads to the drawn hysteresis loops, the lowered squareness of hysteresis loops and high values of low-field magnetic permeability 10.