| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength steel sheet having excellent chemical conversion treatment property and corrosion resistance after electrodeposition coating even when the content of Si or Mn is high, and to provide its manufacturing method.SOLUTION: When continuously sintering a steel sheet containing, by mass%, C:0.03 to 0.35%, Si:0.01 to 0.50%, Mn:3.6 to 8.0%, Al:0.001 to 1.00%, P≤0.10%, S≤0.010% and the balance Fe with inevitable impurities, the dew point is set at -40°C or less in an atmosphere at temperature inside of a firing furnace in a range of 550°C to A°C, where A:600≤A≤750, during a heating process. |
