| 摘要 |
PROBLEM TO BE SOLVED: To obtain the inexpensive ferritic stainless steel plate easily improving the rigging property without deteriorating the mechanical property by containing the specified quantity of Cr, containing the specified quantity of B in the surface layer part and moreover containing the specified quantity of B in the central part. SOLUTION: By weight, 10-23% Cr is contained into this steel plate. Corrosion resistance is insufficient at < the lower limit and ductility and workability are lowered at > the upper limit. B of <30 ppm is specified to contain in the surface layer part of <=10% of the whole plate thickness from the surface. When B of >= this value is added, a hot surface flaw is easily generated. B within the range of 30-300 ppm is specified to contain in the central part of >=35% of the whole plate thickness from the surface. The (γ) phase is necessitated to finely disperse within the ferritic grain by adding B in the central part of the plate thickness. The effect is not expected when the content of B is < the lower limit, the effect is no more improved even though B exceeding the upper limit is added, the quantity of (γ) phase is reduced, whereby the rigging improving effect is reduced.
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