| 摘要 |
The invention relates to non-grain oriented magnetic steel sheets which can be produced as final annealed and as a non-final annealed types in such a way that they have improved magnetic polarisation and reduced magnetic reversal losses compared with the previously achieved values. This is achieved in that a suitably composed steel, during its cooling starting from a maximum initial temperature of 1,300° C., passes through a temperature range with substantially complete exclusion of a purely austenitic structure (gamma phase), in which range it comprises an austenite/ferrite dual phase multi-structure (alpha, gamma multi-phases), so the magnetic steel sheet, after hot rolling, etching, cold rolling and annealing of the hot strip obtained after hot rolling, has a magnetic polarisation J2500>=1.74 T, measured in the longitudinal direction of the strip or sheet and at a magnetic field strength of 2,500 A/m and a value P1.5(50) of the magnetic losses of <4.5 W/kg, measured in the longitudinal direction of the strip at J=1.5 T and a frequency f=50 Hz.
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