Abstract: One aspect of this ferritic stainless steel sheet contains, by mass %, C: 0.03% or less, N: 0.05% or less, Si: 1% or less, Mn: 1.2% or less, Cr: 14% or more and 28% or less, Nb: 8(C+N) or more and 0.8% or less, and Al: 0.1% or less, with a balance being Fe and inevitable impurities, in which a film satisfying Expression 1 is formed in a surface thereof. df×Crf+5(Sif+3Alf)?2.0??(Expression 1) In Expression 1, df represents a thickness (nm) of the film, Crf represents a Cr cationic fraction in the film, Sif represents a Si cationic fraction in the film, and Alf represents an Al cationic fraction in the film.

Abstract: This ferritic stainless steel sheet contains, by mass %: C: 0.02% or less, N: 0.02% or less, Si: 0.05% to 0.80%, Mn: 0.05% to 1.00%, P: 0.04% or less, S: 0.01% or less, Cr: 12% to 20%, Cu: 0.80% to 1.50%; Ni: 1.0% or less, Mo: 0.01% to 2.00%, Nb: 0.30% to 1.00%, Ti: 0.01% to less than 0.25%, Al: 0.003% to 0.46%, V: 0.01% to less than 0.15%, and B: 0.0002% to 0.0050%, with a remainder of Fe and inevitable impurities, wherein the following formulae (1) and (2) are satisfied, and an average Cu concentration in an area from a surface to a depth of 200 nm is 3.00% or less, in the case of Mn<0.65%, 1.44×Si—Mn?0.05?0??(1), and in the case of Mn?0.65%, 1.10×Si+Mn?1.19?0??(2).

Abstract: An aspect of a ferritic stainless steel contains, by mass %: C: 0.03% or less; N: 0.03% or less; Si: more than 0.1% to 1% or less; Mn: 0.02% to 1.2%; Cr: 15% to 23%; Al: 0.002% to 0.5%; and either one or both of Nb and Ti, with the remainder being Fe and unavoidable impurities, wherein Expression (1) and Expression (2) illustrated below are satisfied, an oxide film is formed on a surface thereof, and the oxide film contains Cr, Si, Nb, Ti and Al in a total cationic fraction of 30% or more, 8(C+N)+0.03?Nb+Ti?0.6??(1) Si+Cr+Al+{Nb+Ti?8(C+N)}?15.5??(2).

Abstract: The stainless steel of the first embodiment includes C: 0.001 to 0.02%, N: 0.001 to 0.02%, Si: 0.01 to 0.5%, Mn: 0.05 to 0.5%, P: 0.04% or less, S: 0.01% or less, Ni: more than 3% to 5%, Cr: 11 to 26%, and either one or both of Ti: 0.01 to 0.5% and Nb: 0.02 to 0.6%, and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the second embodiment has an alloy composition different from those of the first and third embodiments and satisfies the formula (A): Cr+3Mo+6Ni?23 and formula (B): Al/Nb?10 and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the third embodiment has an alloy composition different from those of the first and second embodiments and includes either one or both of Sn: 0.005 to 2% and Sb: 0.005 to 1% and contains as the remainder, Fe and unavoidable impurities.

Abstract: The stainless steel of the first embodiment includes C: 0.001 to 0.02%, N: 0.001 to 0.02%, Si: 0.01 to 0.5%, Mn: 0.05 to 0.5%, P: 0.04% or less, S: 0.01% or less, Ni: more than 3% to 5%, Cr: 11 to 26%, and either one or both of Ti: 0.01 to 0.5% and Nb: 0.02 to 0.6%, and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the second embodiment has an alloy composition different from those of the first and third embodiments and satisfies the formula (A): Cr+3Mo+6Ni?23 and formula (B): Al/Nb?10 and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the third embodiment has an alloy composition different from those of the first and second embodiments and includes either one or both of Sn: 0.005 to 2% and Sb: 0.005 to 1% and contains as the remainder, Fe and unavoidable impurities.

Abstract: This ferritic stainless steel for components of an automobile exhaust system includes, in terms of percent by mass: C: ?0.015%; Si: 0.01% to 0.50%; Mn: 0.01% to 0.50%; P: ?0.050%; S: ?0.010%; N: ?0.015%; Al: 0.010% to 0.100%; Cr: 16.5% to 22.5%; Ni: 0.5% to 2.0%; and Sn: 0.01% to 0.50%, and further includes either one or both of Ti: 0.03% to 0.30% and Nb: 0.03% to 0.30%, with a remainder being Fe and inevitable impurities.

Abstract: A ferritic stainless steel sheet for EGR coolers includes at least, by mass % C: 0.03% or less, N: 0.05% or less, Si: 0.1% to 1%, Mn: 0.02% to 2%, Cu: 0.2% to 1.5%, Cr: 15% to 25%, Nb: 8 (C+N) % to 1%, Al: 0.5% or less, and Fe and inevitable impurities as the balance, wherein the steel sheet further includes, by mass %, Ti at an amount fulfilling the following formulae (1) and (2), and Cr and Cu are included at amounts fulfilling the following formula (3), Ti-3N?0.03??(1), 10(Ti-3N)+Al?0.5??(2), and Cr+2.3Cu?18??(3).

Abstract: This ferritic stainless steel with excellent brazeability includes, in terms of mass percent, 0.03% or less of C, 0.05% or less of N, 0.015% or more of C+N, 0.02 to 1.5% of Si, 0.02 to 2% of Mn, 10 to 22% of Cr, 0.03 to 1% of Nb, and 0.5% or less of Al, and further includes Ti in a content that satisfies the following formulae (1) and (2), with the remainder composed of Fe and unavoidable impurities. Ti—3N?0.03??(1) 10(Ti—3N)+Al?0.5??(2) (Here, the atomic symbols in formulae (1) and (2) indicate the content (mass %) of the respective element, and the numerical values that precede the atomic symbols are constants.

Abstract: The present invention provides Cr-containing steel superior in heat fatigue characteristics, that is, Cr-containing steel superior in heat fatigue characteristics, characterized by containing, by mass %, C: 0.01% or less, N: 0.015% or less, Si: 0.8 to 1.0%, Mn: 0.2 to 1.5%, P: 0.03% or less, S: 0.01% or less, Ni: 0.2% or less, Cu: 0.2% or less, Cr: 13 to 15%, Mo: 0.1% or less, Nb: 0.3 to 0.5%, Ti: 0.05 to 0.2%, V: 0.01 to 0.2%, Al: 0.015 to 1.0%, and B: 0.0002 to 0.0010%, satisfying (Nb+1.9×Ti)/(C+N)?50, and having a balance of Fe and unavoidable impurities, wherein a 0.2% yield strength at 800° C. after aging at 800° C. for 100 hours or more is 20 MPa or more and a drawability value at 200° C. is 35% or more and wherein a soluble Nb amount+soluble Ti amount after aging at 800° C. for 100 hours or more is 0.08% or more.

Abstract: The stainless steel of the first embodiment includes C: 0.001 to 0.02%, N: 0.001 to 0.02%, Si: 0.01 to 0.5%, Mn: 0.05 to 0.5%, P: 0.04% or less, S: 0.01% or less, Ni: more than 3% to 5%, Cr: 11 to 26%, and either one or both of Ti: 0.01 to 0.5% and Nb: 0.02 to 0.6%, and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the second embodiment has an alloy composition different from those of the first and third embodiments and satisfies the formula (A): Cr+3Mo+6Ni?23 and formula (B): Al/Nb?10 and contains as the remainder, Fe and unavoidable impurities. The stainless steel of the third embodiment has an alloy composition different from those of the first and second embodiments and includes either one or both of Sn: 0.005 to 2% and Sb: 0.005 to 1% and contains as the remainder, Fe and unavoidable impurities.

Abstract: A ferrite stainless steel for an automobile exhaust system member superior in thermal fatigue strength comprised of, by wt %, C: 0.020% or less, Si: 0.02 to 0.15%, Mn: 0.05 to 0.20%, P: 0.040% or less, S: 0.010% or less, Al: 0.005 to 0.10%, N: 0.020% or less, Cr: 15 to 18%, Mo: 1.5 to 2.0%, Ti: 3×(C+N) to 0.25%, Nb: 0.4 to 0.8%, B: 0.0003 to 0.0050%, the C and N satisfying the relationship of C+N: 0.030% or less, and the Al, Si, and Mn satisfying the relationship of Al×(Si+Mn): 0.001 to 0.020, and a balance of Fe and unavoidable impurities. The 0.2% proof stress at 900° C. before heat treatment in the atmosphere at 900° C. for 300 hours is at least 15 MPa, and a difference of the 0.2% proof stress before and after the heat treatment is not more than 5 MPa.

Abstract: A ferrite stainless steel for an automobile exhaust system member superior in thermal fatigue strength comprised of, by wt%, C: 0.020% or less, Si: 0.02 to 0.15%, Mn: 0.05 to 0.20%, P: 0.040% or less, S: 0.010% or less, Al: 0.005 to 0.10%, N: 0.020% or less, Cr: 15 to 18%, Mo: 1.5 to 2.0%, Ti: 3×(C+N) to 0.25%, Nb: 0.4 to 0.8%, B: 0.0003 to 0.0050%, the C and N satisfying the relationship of C+N: 0.030% or less, and the Al, Si, and Mn satisfying the relationship of Al×(Si+Mn): 0.001 to 0.020, and a balance of Fe and unavoidable impurities. The 0.2% proof stress at 900° C. before heat treatment in the atmosphere at 900° C. for 300 hours is at least 15 MPa, and a difference of the 0.2% proof stress before and after the heat treatment is not more than 5 MPa.

Abstract: A low corrosion resistant pipe 1 is jointed with a high corrosion resistant pipe 2 directly or via a coupling 3. An insulating ceramic film having a thickness of 0.4 .mu.m and a resistivity of 10.sup.8 .OMEGA. cm or more is formed on the outer and inner surfaces of the pipes 1 and 2 at a length L of 60 mm or more from the end of the pipe and on the surface which forms a space when the pipes 1 and 2 are jointed at a coverage ratio of 90% or more to less than 100%.