| 摘要 |
The present invention provides a very thin steel sheet and production method thereof that, in a very thin steel sheet of 0.4 mm or less thickness, enable production at low addition of special elements, simultaneous achievement of both good workability and anti-aging property, and stable passing of even wide coil in a continuous annealing process, which very thin steel sheet and production method are characterized in that it contains, in mass%, C: 0.0004 to 0.0108%, N: 0.0032 to 0.0749%, Si: 0.0001 to 1.99%, Mn: 0.006 to 1.99%, S: 0.0001 to 0.089%, P: 0.001 to 0.069%, and Al: 0.070 to 1.99%; and further one or both of Ti and Nb at Ti: 0.0005 to 0.0804% and Nb: 0.0051 to 0.0894%, within the range of Ti + Nb: 0.0101 to 0.1394%; further satisfies the relationships of N - C ‰¥ 0.0020%, C + N ‰¥ 0.0054%, Al / N > 10, (Ti + Nb) / Al ‰¤ 0.8, (Ti / 48 + Nb / 93) x 12 / C ‰¥ 0.5, and 0.31 < (Ti / 48 + Nb / 93) / (C / 12 + N / 14) ‰¤ 2.0; has a balance of iron and unavoidable impurities; and has a thickness of 0.4 mm or less. |
