Nippon Steel Sumitomo Metal Corporation

Chie Hama

Yoshiyuki Ushigami

Kenichi Murakami

Shuichi Nakamura

Norikazu Fujii

Kazumi Mizukami

Norihiro Yamamoto

Masahide Uragoh

Isao Iwanaga

A predetermined steel containing Te: 0.0005 mass % to 0.0050 mass % is heated to 1320&#xb0; C. or lower to be subjected to hot rolling, and is subjected to annealing, cold rolling, decarburization annealing, and nitridation annealing, and thereby a decarburized nitrided steel sheet is obtained. Further, an annealing separating agent is applied on the surface of the decarburized nitrided steel sheet and finish annealing is performed, and thereby a glass coating film is formed. The N content of the decarburized nitrided steel sheet is set to 0.0150 mass % to 0.0250 mass % and the relationship of 2&#xd7;[Te]+[N]&#x2266;0.0300 mass % is set to be established. Note that [Te] represents the Te content and [N] represents the N content.

Manufacturing method of grain-oriented electrical steel sheet

In a method of manufacturing a grain-oriented electrical steel sheet including a nitriding treatment (step S) and adopting so-called 'low-temperature slab heating', the finish temperature of finish rolling in hot rolling (step S) is set to 950&#xb0; C. or below, the cooling is started within 2 seconds after completion of the finish rolling, and a steel strip is coiled at 700&#xb0; C. or below. The cooling rate over the duration from the end of finish rolling to the start of coiling is set to 10&#xb0; C./sec or above. In annealing (step S) of the hot-rolled steel strip, the heating rate in the temperature range from 800&#xb0; C. to 1000&#xb0; C. is set to 5&#xb0; C./sec or above.

Method of manufacturing grain-oriented electrical steel sheet

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Tokyo, Japan

Chie Hama