Nippon Steel Nisshin Co., Ltd.

Nisshin Steel Co., Ltd.

Nippon Steel Stainless Steel Corporation

Kazunari Imakawa

Satoshi Suzuki

Manabu Oku

Sadayuki Nakamura

Yoshiaki Hori

Yasuhiro Ehara

Yoshikazu Tai

Osamu Yamamoto

Takeo Tomita

Atsushi Sugama

Kazuyuki Kageoka

Yoshitomo Fujimura

Hiroaki Shichi

Nobuhisa Ebihama

Naohito Kumano

Seiji Mitsunaga

Tomoaki Saida

Yoshihide Naruse

Isamu Hayakawa

Akira Hironaka

Yutaka Yakushijin

Provided is a black stainless steel sheet that has excellent weldability, that can ensure good toughness and corrosion resistance, and that can maintain the blackness of the surface thereof, even after being welded. This black ferrite-based stainless steel sheet having excellent weldability includes, as a base, a stainless steel containing, in mass %, 0.020% or less of C, 1.0% or less of Si, 0.35% or less of Mn, 0.04% or less of P, 0.005% or less of S, 11-25% of Cr, 1.0% or less of Mo, 0.020% or less of N, 0.4% or less of Al, 10(C+N) to 0.3% of Ti, 0.05% or less of Nb, and 0.01% or less of O, and has a surface in which an oxide coating is formed on the base, wherein the surface has a lightness index (L*) satisfying L*&#x2264;45, chromaticity indices (a*, b*) satisfying &#x2212;5&#x2264;a*&#x2264;5 and &#x2212;5&#x2264;b*&#x2264;5, and a blackness (E) satisfying E=(L*2+a*2+b*2)1/2&#x2264;45.

Black ferrite-based stainless steel sheet

A Ti-containing ferritic stainless steel sheet for an exhaust pipe flange member has a composition containing, in mass percentage, from 0.003 to 0.030% of C, 2.0% or less of S i, 2.0% or less of Mn, 0.050% or less of P, 0.040% or less of S, from 10.0 to 19.0% of Cr, 0.030% or less of N, from 0.07 to 0.50% of Ti, from 0.010 to 0.20% of Al, from 0 to 1.50% of Mo, and from 0 to 0.0030% of B, with the balance Fe and unavoidable impurities, has a K value of 150 or more, has a sheet surface hardness of 170 HV or less, and has a sheet thickness of from 5.0 to 11.0 mm. The K value equals &#x2212;0.07&#xd7;Cr&#x2212;6790&#xd7;Free(C+N)&#x2212;1.44&#xd7;d+267, wherein Free(C+N) corresponds to the solid-dissolved (C+N) concentration (% by mass), and d represents an average crystal grain diameter (&#x3bc;m).

Ti-containing ferritic stainless steel sheet for exhaust pipe flange member, production method, and flange member

Provided is a stainless steel material for a diffusion bonding jig in which deformation of bonding members is suppressed while maintaining diffusion bonding properties of the bonding members, and in which releasability (detachability of a bonding member from a release member) after diffusion bonding treatment is excellent. An embodiment of the present invention provides a stainless steel material for a diffusion bonding jig having excellent deformation suppressibility and releasability, the material being a stainless steel material including 1.5 mass % or more of Si, and a ratio (Fr/Fp) of the high-temperature strength (Fr) of the stainless steel material at 1000&#xb0; C. to the high-temperature strength (Fp) of a bonding member at 1000&#xb0; C. being 0.9 or more, the bonding member to be bonded by diffusion bonding. The stainless steel material preferably includes C: 0.1 mass % or less, Si: 1.5 to 5.0 mass %, Mn: 2.5 mass % or less, P: 0.06 mass % or less, S: 0.02 mass % or less, Ni: 8.0 to 15.0 mass %, Cr: 13.0 to 23.0 mass %, and N: 0.2 mass % or less.

Stainless steel material for diffusion bonding jig

Provided is a method of manufacturing a heat exchanger by diffusion bonding in which deformation of bonding members as stainless steel plates is suppressed, and releasability (detachability of a bonding member from a release member) after diffusion bonding treatment is excellent. Provided is a method of manufacturing a heat exchanger, the method including layering a plurality of bonding membersmade of stainless steel, and applying heat and pressure to effect diffusion bonding of the bonding members, in which release membersare arranged on the both surface sides of the bonding members, and holding jigsare arranged so as to sandwich the bonding membersthrough the release members, and pressing is then performed through the holding jigswith a pressure device, and in which the diffusion bonding is performed using a combination of the release membersand the bonding members, the release membersincluding a steel material containing 1.5 mass % or more of Si, and a ratio (Fr/Fp) of the high-temperature strength (Fr) of the release membersat 1000&#xb0; C. to the high-temperature strength (Fp) of the bonding membersat 1000&#xb0; C. being 0.9 or more.

Method of manufacturing heat exchanger

A ferritic stainless steel material excellent in vibration damping capability has a composition containing, by mass %, from 0.001 to 0.04% of C, from 0.1 to 2.0% of Si, from 0.1 to 1.0% of Mn, from 0.01 to 0.6% of Ni, from 10.5 to 20.0% of Cr, from 0.5 to 5.0% of Al, from 0.001 to 0.03% of N, from 0 to 0.8% of Nb, from 0 to 0.5% of Ti, from 0 to 0.3% of Cu, from 0 to 0.3% of Mo, from 0 to 0.3% of V, from 0 to 0.3% of Zr, from 0 to 0.6% of Co, from 0 to 0.1% of REM, from 0 to 0.1% of Ca, the balance of Fe and unavoidable impurities, and has ferrite single phase matrix with crystal grains of average crystal grain diameter of from 0.3 to 3.0 mm and a residual magnetic flux density of 45 mT or less.

High Al-content vibration-damping ferritic stainless steel material, and production method

A plate-type heat exchanger may include a housing. The housing may include a plurality of rectangular plate-like components that are box-like components each having the same shape and having a standing wall section along a peripheral edge. One of the box-like components may be layered on another components reversed in the horizontal direction to form a layered structure having an upper layer component and a lower layer component such that an upper portion of a standing wall section of the lower layer component of the layered structure is fit into a lower portion of a standing wall section of the upper layer component of the layered structure. The angle (&#x3b8;) of the standing wall sections may be &#x3b8;&#x2264;30&#xb0;, and at least a portion of a contact region between the upper portion and the lower portion may be joined by solid phase diffusion bonding.

Plate-type heat exchanger and method for producing same

To provide a heat resistant metal gasket that is controlled to have a strength level (ordinary temperature hardness) capable of facilitating processing, and has excellent gas leak resistance. An austenitic stainless steel sheet for a metal gasket, having a chemical composition containing from 0.015 to 0.200% of C, from 1.50 to 5.00% of Si, from 0.30 to 2.50% of Mn, from 7.0 to 17.0% of Ni, from 13.0 to 23.0% of Cr, and from 0.005 to 0.250% of N, all in terms of percentage by mass, containing, as necessary, at least one of Mo, Cu, Nb, Ti, V, Zr, W, Co, B, Al, REM (rare-earth element except for Y), Y, Ca and Mg, with the balance of Fe and unavoidable impurities, having an ordinary temperature hardness of 430 HV or less, having a half width of a peak of an austenite crystal (311) plane in an X-ray diffraction pattern of a cross section perpendicular to a sheet thickness direction of from 0.10 to 1.60&#xb0;, and having a surface roughness Ra of 0.30 &#x3bc;mm or less.

Austenitic stainless steel sheet for gasket, and gasket

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Tokyo, Japan

Kazunari Imakawa