The rolling flow sheet for tested oriented silicon steel cold-rolled sheet (/% : 0.050C

3.20Si

0.15Mn

0.003S

0.023Als

0.0090N) is 220 mm cast slab-hot rolled to 1.8 mm plate-normalized at 1120℃. for 2.4 min- cold- rolled to 0.23 min and 0.18 mm sheet

then decarburized at 850℃ for 5 min and nitriding at 700°C for 2 min

after treated the C content in sheet is 0.0020% and the N content in sheet is 0.0180% . The effect of N

2

content (25%

50%

75% and 90% ) in atmosphere during 17℃/h annealing heating up period at 600~1200 ℃ on magnetic performance of 0.23 mm and 0.18 mm cold-rolled sheet of low-temperature heati

ng oriented silicon steel has been tested and studied. Results show that during 600〜1200℃ heating up period with using 50% N

2

and 75%

N

2

atmosphere the 0.23 mm sheet of low-temperature heating oriented silicon steel has better magnetic performance

its iron loss is 0.9 W/kg

and with using 75%

N

2

atmosphere the 0.18 mm sheet of low-temperature heating oriented silicon steel has optimum magnetic performance

its iron loss is 0.8 W/kg

and with using 25% N

2

the magnetic performance of 0.18 mm sheet is poorest i. e. iron loss 1.63 W/kg