Method of manufacturing cold-rolled nonoriented electro-6 magnetic steel sheet and product electromagnetic steel sheet
Abstract
Abstract IN THE METHOD OF MANUFACTURING A COLD-ROLLED NONORIENTED ELECTROMAGNETIC STEEL SHEET COMPRISING SI IN AN AMOUNT OF 1.0-4.0% BY WEIGHT, ACID SOLUBLE AL IN AN AMOUND OF 0.1-3.0% BY WEIGHT AND THE REST BEING IRON, COMPRISING THE ORDINARY PRODUCTION STEPS OF DECARBURIZATION, AT LEAST ONE COLD-ROLLING STEP, AND A FINAL HEAT-TREATMENT SUBSEQUENT TO THE FINAL COLD-ROLLING STEP (INCLUDING SKIN PASS OR TEMPER ROLLING), THE IMPROVEMENT WHICH COMPRISES THE DECARBURIZATION TREATMENT BEING CARRIED OUT IN THE PRODUCTION STEPS BEFORE THE FINAL COLD-ROLLING STEP, THE INNER OXIDIZED LAYER PRESENT IN THE SURFACE PART OF THE STEEL BEING REMOVED AFTER THE DECARBURIZATION TREATMENT BUT BEFORE THE FINAL COLD-ROLLING STEP; ALL THE HEAT-TREATMENTS AFTER THE REMOVAL OF THE INNER OXIDIZED LAYER BEING CARRIED OUT IN A NON-OXIDIZING ATMOSPHERE WHICH CONTAINS WATER AND HYDROGEN IN SUCH AMOUNTS THAT THE RATIO OF THE PARTIAL PRESSURE OF STEAM FORMED DURING THE HEATTREATMENT STEPS TO THE PARTIAL PRESSURE OF HYDROGEN IS LESS THAN 0.05 TO AVOID THE RE-FORMING OF AN INNER OXIDIZED LAYER.
Inventors
- 👤 O Honjo
- 👤 I Matsushita
- 👤 K Tanada
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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