PRODUCTION OF GRAIN-ORIENTED AND NONORIENTED SILICON STEEL SHEET HAVING LOW CORE LOSS AND HIGH MAGNETIC FLUX DENSITY AND CONTINUOUS ANNEALING EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To provide new technology capable of industrially stably producing a silicon steel sheet combining low core loss and high magnetic flux density by utilizing the magnetic field. ;SOLUTION: At the time of producing a grain-oriented silicon steel sheet by a series of process in which a steel slab contg., by weight, ≤0.095% C, 1.5 to 7.0% Si and 0.03 to 2.50% Mn is subjected to hot rolling and cold rolling and is subjected to continuous primary recrystallization annealing and final finish annealing, the average grain size of crystals composing the steel sheet before the final cold rolling is controlled to ≥10 μm, and the continuous primary recrystallization annealing satisfying the conditions in which (1) the average temp. rising rate at ≥500°C at the time of temp. rising is controlled to ≥4°C/s, (2) the annealing temp. is controlled to the range of 700 to 900°C, (3) the AC. or DC. magnetic field of ≥1.5 T is applied to the steel sheet at least at ≥500°C for ≥0.03 sec in the rolling direction and (4) the tensile strength applied to the steel sheet at least at the time of applying the magnetic field is controlled to ≤2.0 kgf/mm2 is executed.;COPYRIGHT: (C)2000,JPO