THREE NEW Fe-BASED MICROCRYSTALLINE ALLOYS WITH SUPERIOR MAGNETIC PROPERTIES

Three new Fe-based microcrystalline alloys,i.e.,Fe_(73.1)Cu_(1.2)Nb_(3.2)Si_(12 5)B_(10),Fe_(73)Cu_1Nb_(1.5)Mo_2Si_(12.5)B_(10) and Fe_(73)Cu_1Zr_3C_(0.5)Mo_Si_(12.5)B_(10),were developed with su-perior magnetic properties.e.g.,high relative initial permeability of μ_i~15×10~4,lowcoercivity of H_c1.0A/m,high effective permeability and low core losses in a consid-crable wide frequency range and high pulse-magnetic permeability under narrow pulse.The optimum value of relative effective permeability,μ_5~1 is 16×10~4 under condition off=1 kHz and H_m=0.4 A/m.The optimum values of core loss reach 57.9 30.2 and 68W/kg under condition of f=50.100.100 KHz and B_m=0.5,0.2,0.3 T,respectively.These three alloys have superior stability of magnetic properties.Initial permeabilitymay be not changed during heating at 130℃ up to 216 h.The main crystalline phaseis ordered phase Fe_((75)+y)Si_((25)-y) which is ultrafine particles of average size 10—20 nm.