Patent ID: 7377986

Claim:
A method for producing a non-oriented electrical steel comprising the steps of: (a) preparing a non-oriented electrical steel melt having a composition in weight % comprising: up to about 6.5% silicon, up to about 5% chromium, up to about 0.05% carbon, up to about 3% aluminum, up to about 3% manganese, and the balance being substantially iron and residuals; (b) casting a steel slab from said steel melt; (c) heating said steel slab to a temperature less than T max and greater than T min as defined by: T min , ° C.=921−5998(%C)−106(%Mn)+135(%P)+78.5(%Si)+107(%Al)−11.9(%Cr)+896(%N)+8.33(%Cu)−146(%Ni)+173(%Mo) T max , ° C.=1479+3480(%C)+158(%Mn)−347(%P)−121(%Si)−275(%Al)+1.42(%Cr)−195(%N)+44.7(%Cu)+140(%Ni)−132(%Mo) (d) hot rolling said slab to a hot rolled strip wherein said hot rolling provides a nominal strain of at least 700 using the equation: ɛ nominal = [ 2 ⁢ π ⁢ ⁢ n t i ⁢ D ⁡ ( t i - t f ) ⁢ ( 1.25 - t f 4 ⁢ t i ) ] 0.15 ⁢ exp ⁡ ( 7616 T ) ⁢ ln ⁡ ( t i t f ) ; ⁢ and , (e) finish annealing said strip at a temperature less than T as defined by: T , ° C.=759−4430(%C)−194(%Mn)+445(%P)+181(%Si)+378(%Al)−29.0(%Cr)−48.8(%N)−68.1(%Cu)−235(%Ni)+116(%Mo).