PROCESS FOR PRODUCTION OF UNIDIRECTIONAL ELECTROMAGNETIC STEEL SHEET

• Main Authors: IWANAGA ISAO, YAMAMOTO NORIHIRO, HAMA CHIE, USHIGAMI YOSHIYUKI, URAGOH MASAHIDE, MURAKAMI KENICHI, FUJII NORIKAZU
• Format: Patent
• Language: English; Korean
• Published: 07.01.2013
• Subjects: ALLOYS; BASIC ELECTRIC ELEMENTS; CHEMISTRY; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; INDUCTANCES; MAGNETS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; PERFORMING OPERATIONS; PUNCHING METAL; ROLLING OF METAL; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS

In a method of manufacturing a grain-oriented electrical steel sheet including a nitriding treatment (step S7) and adopting so-called "low-temperature slab heating", the finish temperature of finish rolling in hot rolling (step S2) is set to 950°C or below, the cooling is started within 2 seconds after completion of the finish rolling, and a steel strip is coiled at 700°C or below. The cooling rate over the duration from the end of finish rolling to the start of coiling is set to 10°C/sec or above. In annealing (step S3) of the hot-rolled steel strip, the heating rate in the temperature range from 800°C to 1000°C is set to 5°C/sec or above.