| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an austenitic stainless steel sheet having corrosion resistance, hydrogen brittleness resistance and forming workability required for a solid high polymer type fuel cell separator material and satisfying cost effectiveness, to provide its production method, and to provide its forming method. <P>SOLUTION: The stainless steel for a solid high polymer type fuel cell separator has a composition containing suitable amounts of C, Si, Mn, Ni, Cr, Mo, Cu and N, and the balance Fe with inevitable impurities, and has a microstructure of an σ phase of ≤5% area ratio, and the balance austenitic phase. The average crystal grain size of the stainless steel is 1 to 40 μm, GI value is 55 to 150, CI value is 30 to 65, and Tσ value is 550 to 1,050, and its sheet thickness is preferably controlled to 0.02 to 0.2 mm. In the production method, after hot rolling, cold rolling is performed at a total rolling ratio of 90 to 98%. The resultant steel sheet is held at 1,070 to 1,200°C for 1 to 1,800 s for solution treatment, and then cooled to 450°C at 10 to 500°C/s. In the forming method, press forming or roll forming is performed at -25 to 10°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
