High-purity ferritic stainless steel sheet with excellent oxidation resistance and high-temperature
2022-06-06
2700
859K
0
The present invention provides a low-alloy high-purity ferritic stainless steel sheet provided with improved oxidation resistance and high-temperature strength by utilizing Sn addition in trace amounts without relying on excessive alloying of Al and Si which reduces fabricability and weldability or addition of rare elements such as Nb, Mo, W, and rare earths, and a process for producing the same. The high-purity ferritic stainless steel sheet includes C : 0.001 to 0.03%, Si : 0.01 to 2%, Mn : 0.01 to 1.5%, P : 0.005 to 0.05%, S : 0.0001 to 0.01%, Cr : 16 to 30%, N : 0.001 to 0.03%, Al : 0.05 to 3%, and Sn : 0.01 to 1% (% by mass), with the remainder being Fe and unavoidable impurities. A stainless steel slab having such steel components is heated, wherein an extraction temperature is 1100 to 1250° C., and a winding temperature after hot rolling is 650° C. or lower. A hot-rolled sheet is annealed at 900 to 1050° C., and cooled at 10° C./sec or less over a temperature range of 550 to 850° C.