Nippon Steel & Sumikin Stainless Steel Corporation

Kabushiki Kaisha Nihon Micronics

Nippon Steel Corporation

Disco Corporation

Nippon Steel & Sumitomo Metal Corporation

Arcelor France

Sumikin Stainless Steel Corporation

Dai Nippon Printing Co., Ltd.

Ken Kimura

Junichi Hamada

Akihiko Takahashi

Eiichiro Ishimaru

Shinichi Teraoka

Masaharu Hatano

Yoshiharu Inoue

Masaaki Kobayashi

Takashi Morohoshi

Haruhiko Kajimura

Naoto Ono

Norihiro Kanno

Takayuki Umahashi

Toyohiko Kakihara

Shigeyuki Gotoh

Jun Takahashi

Yoshihito Yamada

Satoshi Hashimoto

Katsuyuki Kakizaki

Yuuji Koyama

Masafumi Azuma

Manabu Takahashi

Masao Kikuchi

Naoki Yoshinaga

Hiroshi Shuto

Natsuko Sugiura

Eichi Osato

Akifumi Sakakibara

Nobuhiko Hiraide

Toshio Tanoue

Hiroaki Nakayama

Masashi Hasegawa

Hiroyuki Matsuyama

Masanori Ueno

Yuuki Kanzawa

Satoshi Akamatsu

Toshinaru Kayahara

Masayuki Tendo

Satoshi Tateiwa

Yasuhiro Matsukawa

Naoto Hansaki

Akihito Yamagishi

Yoshio Okabe

Kouji Doi

A Cr-containing ferritic stainless steel sheet is desired with improved corrosion resistance and rust resistance as well as improved ridging resistance. To achieve these results, the ferritic stainless steel sheet derives the relationship between Ap, which shows the &#x3b3;-phase rate at 1100&#xb0; C. due to a predetermined ingredient, and Sn in ferritic stainless steel which becomes a dual phase structure of &#x3b1;+&#x3b3; in the hot rolling temperature region, applies and adds Sn, and hot rolls the steel to give a total rolling rate of 15% or more in 1100&#xb0; C. or higher hot rolling to thereby obtain ferritic stainless steel sheet which has good ridging resistance, which also has excellent corrosion resistance and rust resistance, and which can be applied to general durable consumer goods, wherein 0.060&#x2264;Sn&#x2264;0.634&#x2212;0.0082Ap and 10&#x2264;Ap&#x2264;70.

Ferritic stainless steel plate which has excellent ridging resistance and method of production of same

A ferritic stainless steel sheet containing, by mass %, C: 0.020% or less, Cr: 10.0% to 25.0%, N: 0.020% or less, Sn: 0.010% to 0.50%, and one or more of Ti: 0.60% or less, Nb: 0.60% or less, V: 0.60% or less, and Zr: 0.60% or less so as to satisfy Equation (1): (Ti/48+V/51+Zr/91+Nb/93)/(C/12+N/14)&#x2265;1.0, wherein a difference between a stress &#x3c3;1 (N/mm) after prestrain imparting tensile deformation with 7.5% of strain, and an upper yield stress &#x3c3;2 (N/mm) when the steel sheet is subjected to heat treatment at 200&#xb0; C. for 30 minutes and then to tension again after the tensile deformation is 8 or less.

Ferritic stainless steel sheet exhibiting small increase in strength after aging heat treatment, and method of producing the same

This hot-rolled ferritic stainless steel sheet has a steel composition containing, in terms of % by mass: 0.02% or less of C; 0.02% or less of N; 0.1% to 1.5% of Si; 1.5% or less of Mn; 0.035% or less of P; 0.010% or less of S; 1.5% or less of Ni; 10% to 20% of Cr; 1.0% to 3.0% of Cu; 0.08% to 0.30% of Ti; and 0.3% or less of Al, with the balance being Fe and unavoidable impurities, and the hot-rolled ferritic stainless steel sheet has a Vickers hardness of less than 235 Hv.

Hot rolled ferritic stainless steel sheet, method for producing same, and method for producing ferritic stainless steel sheet

A hot-rolled steel sheet has a composition containing: in mass %, C: 0.01 to 0.2%; Si: 2.5% or less; Mn: 4.0% or less; P: 0.10% or less; S: 0.03% or less; Al: 0.001 to 2.0%; N: 0.01% or less; and O: 0.01% or less, and one kind or a total of two kinds of Ti and Nb for 0.01 to 0.30%. An average effective crystal grain diameter at a sheet thickness &#xbc; part is 10 &#x3bc;m or less, and an average effective crystal grain diameter at a part of a range of 50 &#x3bc;m from a surface is 6 &#x3bc;m or less. A structure of the steel sheet is tempered martensite or lower bainite, and a volume fraction thereof is 90% or more as a total.

Hot-rolled steel sheet

A ferritic stainless steel sheet having ridging resistance contains, by mass, 0.025 to 0.30% C, 0.01 to 1.00% Si, 0.01 to 2.00% Mn, 0.050% or less P, 0.020% or less S, 11.0 to 22.0% Cr, and 0.022 to 0.10% N. In addition, Ap, which is defined as 420C+470N+23Ni+9Cu+7Mn&#x2212;11.5(Cr+Si)&#x2212;12Mo&#x2212;52Al&#x2212;47Nb&#x2212;49Ti+189 wherein each of Sn, C, N, Ni, Cu, Mn, Cr, Si, Mo, Al, Nb, and Ti denotes the content of the element, satisfies 10&#x2266;Ap&#x2266;70. Furthermore, a content of Sn satisfies 0.060&#x2266;Sn&#x2266;0.634&#x2212;0.0082Ap. Residual ingredients are Fe and unavoidable impurities, and a metal structure of the steel sheet is a ferrite single phase. The ferritic stainless steel sheet has a ridging height of less than 6 &#x3bc;m. This ferritic stainless steel sheet improves the corrosion resistance and rust resistance of Cr-containing ferritic stainless steel as well as the ridging resistance.

The present invention provides a ferritic stainless steel casting and a sheet thereof excellent in deep drawability, punch stretchability and ridging resistance and a method for producing the casting and the sheet. In the present invention, a chemical composition is controlled so that the amounts of C, N, Si, Mn, P and Ti may be reduced to the utmost for securing high workability and, on the basis of the chemical composition, the roping and ridging of a steel sheet product is reduced by adding Mg, thus dispersing Mg containing oxides that accelerate the formation of nuclei for solidification and, resultantly, suppressing the development of coarse columnar crystals in a casting. The present invention is characterized in that the average composition of the Mg containing oxides dispersing in a casting satisfies the following expressions &#x3c;2&#x3e; and &#x3c;3&#x3e;,17.4(AlO)+3.9(MgO)+0.3(MgAlO)+18.7(CaO)&#x2266;500&#x2003;&#x2003;&#x3c;2&#x3e;,(AlO)+(MgO)+(MgAlO)+(CaO)&#x2267;95&#x2003;&#x2003;&#x3c;3&#x3e;.

Ferritic stainless steel casting and sheet and method for producing the same

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&#x2267;23 and formula (B): Al/Nb&#x2267;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.

Stainless steel excellent in corrosion resistance, ferritic stainless steel excellent in resistance to crevice corrosion and formability, and ferritic stainless steel excellent in resistance to crevice corrosion

A contact according to the present invention comprises a plate-shaped first plunger contacting one member, a plate-shaped second plunger contacting the other member in a state of being overlapped with the first plunger and conducting electricity between the one member and the other member in cooperation with the first plunger, and a compression coil spring which is a member coupling the first plunger with the second plunger in a state where contact pieces thereof are in opposite directions from each other, covering outer circumferences of coupling portions of the first plunger and the second plunger, abutting on spring receiving portions of the respective plungers, and supporting the respective plungers to be relatively slidable. In an electrical connecting apparatus, the contacts are incorporated.

Contact and electrical connecting apparatus

This ferrite-austenite stainless steel sheet includes: in terms of mass %, C: 0.1% or less; Cr: 17 to 25%; Si: 1% or less; Mn: 3.7% or less; Ni: 0.6 to 3%; Cu: 0.1 to 3%; and N: 0.06% or more and less than 0.15%, with the remainder being Fe and inevitable impurities, wherein the steel sheet has a two-phase structure consisting of a ferrite phase and an austenite phase, a volume fraction of the austenite phase is in a range of 15 to 70%, and in a sheet plane (ND) of a center of a sheet thickness, grains of the ferrite phase having a crystal orientation satisfying ND//{111}&#xb1;10&#xb0; and grains of the ferrite phase having a crystal orientation satisfying ND//{101}&#xb1;10&#xb0; are present in a total content of 10% by area or more.

Ferrite-austenite stainless steel sheet excellent in ridging resistance and workability and process for manufacturing the same

Electric contact

The invention provides structural component for an automobile, two-wheeled vehicle or railcar excellent in impact-absorption property, shape fixability and flange cuttability, and method for producing the same, which structural component has a hat-like shape including vertical walls and flanges, wherein distal ends of the flanges contain 20 vol % or greater of austenite phase and have a cross-section hardness expressed as Vickers harness of 150&#x2dc;350, and a center regions of the vertical walls have, in a common cross-section with the flanges, a content of deformation-induced martensite phase exceeding that of the distal ends of the flanges by 10 vol % or greater and a cross-section hardness expressed as Vickers hardness that exceeds that of the distal ends of the flanges by 50 or greater.

Structural component for automobile, two-wheeled vehicle or railcar excellent in impact-absorption property, shape fixability and flange cuttability, and method for producing the same

The present invention provides a ferritic stainless steel sheet superior in shapeability containing, by wt %, C: 0.001 to 0.010%, Si: 0.01 to 1.0%, Mn: 0.01 to 1.0%, P: 0.01 to 0.04%, Cr: 10 to 20%, N: 0.001 to 0.020%, Nb: 0.3 to 1.0%, and Mo: 0.5 to 2.0%, wherein the total precipitates are, by wt %, 0.05 to 0.60%. A method of production of a ferritic stainless steel sheet superior in shapeability comprising producing a cold rolling material in the production process so that the Nb-based precipitates become, by vol %, 0.15% to 0.6% and have a diameter of 0.1 &#x3bc;m to 1 &#x3bc;m and/or so that the recrystallized grain size becomes 1 &#x3bc;m to 40 &#x3bc;m and the recrystallization rate becomes 10 to 90%, then cold rolling and annealing it at 1010 to 1080&#xb0; C.

Ferritic stainless steel sheet superior in shapeability and method of production of the same

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Tokyo, Japan

Ken Kimura