Non-oriented silicon steel sheet mfr. - by hot and two-stage cold rolling with annealing

摘要

The mfr. of Si-steel sheets which are non-oriented and have a high magnetic induction and low iron losses is discribed. An ingot or plate of steel contg. is not 0.02%C, 1.6-3.5% Si, 0.2-2.5% Al and 0.1-1.0% Mn and bal. Fe is hot rolled, opt. annealed, cold rolled twice with intermediate annealing to final thickness and final annealed. The S and O contents are controlled to is not 0.005% and is not 0.0025% resp. The ingot during the first cold rolling stage is reduced =20% and the intermediate anneal at 900-1050 degrees C for 3-15 min. promotes grain growth to an av. grain size of =0.07mm. In the second cold rolling stage the reduction is 45-70% and the final anneal is at 930-1000 degrees C for 2-15 min. Non-oriented sheet is used principally for rotors, stators, etc. in rotating machinery. The magnetic induction B50 is =1.67T for a field of 5000A/m and losses in the iron are is not 2.4W/kg, and is not 2.9W/kg at 1.5T and 50Hz for thicknesses of 0.35 and 0.50mm.