Effect Of Cooling Rate On Microstructure And Magnetic Properties Of Cu-alloyed High Silicon Steel

In this paper,Cu-alloyed high silicon steel was annealed at 1000?for 1 hour,and then was cooled with different rates.The microstructure,ordered phases,magnetic domain structure of samples with different cooling rates were observed.The recrystallization texture and magnetic properties were measured.The effect of cooling rate on microstructure,texture and magnetic properties of Cu-alloyed high silicon steel was studied and its mechanism was revealed.The main conclusions are as follows:?1?The effect of cooling rate on microstructure of Cu-alloyed samples was limited.With the decrease of cooling rate,the amount of B2 ordered phase in Cu-alloyed samples decreased firstly and then increased,and its size increased gradually.The amount and size of D03 ordered phase increased gradually.The recrystallization grain size increased and the amount and size of ordered phases decreased with the addition of Cu.?2?The effect of cooling rate on the recrystallization texture of Cu-alloyed samples was very small.With the decrease of cooling rate,the amount of 180°magnetic domain in Cu-alloyed samples increased and the width of magnetic domain decreased gradually.The addition of Cu promoted the formation of?texture and decreased the width of magnetic domain.?3?For low frequency?50Hz?,the total iron loss P_1.0/50.0/50 of Cu-alloyed samples was dominated by hysteresis loss.The hysteresis loss decreased gradually with the increase of ordered phases size.At medium frequency?400Hz?,the ratio of eddy current loss increased.With the increase of ordered phases size and decrease of magnetic domain width,both the hysteresis loss and eddy current loss decreased gradually.Thus,the total iron loss P_1.0/50.0/50 and _P1.0/4001.0/400 decreased with the decrease of cooling rate.The addition of Cu resulted in the increase in recrystallization grain size and decrease in ordered phases amount and magnetic domain width,leading to the reduction of total iron loss.?4?At low magnetic field?800A/m?,the amount of 180°magnetic domain and the size of ordered phases in Cu-alloyed samples increased gradually with the decrease of cooling rate,leading to the increase of magnetic induction B8.Under high magnetic field?5000A/m?,the magnetic induction B50 increased firstly and then decreased with the decrease of cooling rate due to the amount change of ordered phases.The addition of Cu decreased the amount of ordered phases and promoted the formation of?texture,leading to increase of magnetic induction B₈ and B₅₀.