Patent ID: 7819991

Claim:
A ferritic stainless steel sheet for forming a raw material pipe for bellows pipe comprising about 0.015% by mass or less of C, about 1.0% by mass or less of Si, about 1.0% by mass or less of Mn, about 0.04% by mass or less of P, about 0.010% by mass or less of S, about 11% to about 19% by mass of Cr, about 0.015% by mass or less of N, about 0.15% by mass or less of Al, about 1.25% to about 2.5% by mass of Mo, about 0.3% to about 0.7% by mass of Nb, about 0.0003% to about 0.003% by mass of B, and the balance being Fe and incidental impurities, and having a thickness of about 0.5 mm or less, an average crystal grain diameter of about 35 μm or less, a surface roughness Ra of about 0.4 μm or less and a uniform elongation of 15.1% or more.