Jfe Steel Corporation

Kawasaki Steel Corporation

Tokin Corporation

National Institute of Advanced Industrial Science and Technology

Jfe Precision Corporation

Mineo Muraki

Takeshi Imamura

Minoru Takashima

Atsushi Miyazaki

Yoshihiro Yazawa

Osamu Furukimi

Junichiro Hirasawa

Yoshihiro Ozaki

Tomofumi Shigekuni

Kunio Fukuda

Susumu Satoh

Michiro Komatsubara

Toshito Takamiya

Hiroi Yamaguchi

Mitsumasa Kurosawa

Takuya Takashita

Makoto Watanabe

Yukihiro Baba

Kunihiro Senda

Yukihiro Shingaki

Akiri Urata

Makoto Nakaseko

Naomichi Nakamura

Hiroaki Toda

Atsuhito Honda

Kimihiro Ozaki

Akio Fujita

Hoshiaki Terao

Miho Chiba

Kazuaki Tamura

Toshinori Tsuda

Tetsuo Toge

Makoto Yamaki

Kenichi Sadahiro

Raita Wada

Toshihiro Kasamo

Atushi Miyazaki

Yu Kanamori

Koichi Okamoto

Shoichi Sato

Chizuko Goto

Satoshi Koseki

Yasushi Katoh

Setsuo Kakihara

Toshimitsu Nagaya

Provided is a method of manufacturing a soft magnetic dust core. The method includes: preparing coated powder including amorphous powder made of an Fe-B-Si-P-C-Cu-based alloy, an Fe-B-P-C-Cu-based alloy, an Fe-B-Si-P-Cu-based alloy, or an Fe-B-P-Cu-based alloy, with a first initial crystallization temperature Tand a second initial crystallization temperature T; and a coating formed on a surface of particles of the amorphous powder; applying a compacting pressure to the coated powder or a mixture of the coated powder and the amorphous powder at a temperature equal to or lower than T−100 K; and heating to a maximum end-point temperature equal to or higher than T−50 K and lower than Twith the compacting pressure being applied.

Method of manufacturing soft magnetic dust core

This soft magnetic powder is represented by composition formula FeSiBPCuwith the exception of unavoidable impurities. In the composition formula, a, b, c, d and e satisfy 79&#x2264;a&#x2264;84.5 at %, 0&#x2264;b&#x3c;6 at %, 4&#x2264;c&#x2264;10 at %, 4&#x3c;d&#x2264;11 at %, 0.2&#x2264;e&#x3c;0.4 at %, and a+b+c+d+e=100 at %.

Soft magnetic powder, Fe-based nanocrystalline alloy powder, magnetic component and dust core

A treatment solution for an insulation coating of grain-oriented electrical steel sheets includes at least one selected from phosphates of Mg, Ca, Ba, Sr, Zn, Al and Mn; colloidal silica in a proportion of 0.5 to 10 mol in terms of SiO; and a water-soluble vanadium compound in a proportion of 0.1 to 2.0 mol in terms of V, relative to PO:1 mol in the phosphates.

Treatment solution for insulation coating for grain-oriented electrical steel sheets

A treatment solution for insulation coating for grain-oriented electrical steel sheets contains at least one selected from phosphates of Mg, Ca, Ba, Sr, Zn, Al, and Mn; colloidal silica in a proportion of 0.5 to 10 mol in terms of SiOand a water-soluble vanadium compound in a proportion of 0.1 to 2.0 mol in terms of V, relative to PO:1 mol in the phosphates.

Treatment solution for insulation coating for grain-oriented electrical steel sheets and method for producing grain-oriented electrical steel sheet having insulation coating

The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10&#xd7;(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si&#x2266;1.2-0.4 Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.

Soft Cr-containing steel

A treatment solution for an insulation coating for a grain oriented electrical steel sheet includes at least one member selected from phosphates of Mg, Ca, Ba, Sr, Zn, Al, and Mn, and colloidal silica in a proportion of 0.5 to 10 mol in terms of SiOand at least one member selected from permanganates of Mg, Sr, Zn, Ba, and Ca in a proportion of 0.02 to 2.5 mol in terms of metal elements in the permanganates, relative to PO:1 mol in the phosphates.

Treatment solution for insulation coating for grain oriented electrical steel sheet and method for producing grain oriented electrical steel sheet having insulation coating

A treatment solution for insulation coating for grain oriented electrical steel sheet includes at least one member selected from phosphates of Mg, Ca, Ba, Sr, Zn, Al, and Mn, and colloidal silica in a proportion of 0.2 to 10 mol in terms of SiOand a titanium chelate compound in a proportion of 0.01 to 4.0 mol in terms of Ti, relative to PO: 1 mol in the phosphates.

In a grain-oriented electrical steel sheet having phosphate-based coatings, which contain no chromium and which impart a tension, on the surfaces of a steel sheet with ceramic underlying films therebetween, the coating amount of oxygen in the underlying film is 2.0 g/mor more and 3.5 g/mor less relative to both surfaces of the steel sheet. Consequently, a grain-oriented electrical steel sheet with a chromium-less coating is provided. The resulting steel sheet has coating properties at the same level as those of a steel sheet with chromium-containing coatings and realizes high hygroscopicity resistance and a low iron loss without variations.

Grain-oriented electrical steel sheet and method for manufacturing grain-oriented electrical steel sheet

The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10&#xd7;(C+N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si&#x2266;1.2&#x2212;0.4Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.

A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5% Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18&#x2266;Nb/(C+N)+2Ti/(C+N)&#x2266;60, wherein C, N, Nb, and Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.

Ferritic stainless steel sheet with excellent workability and method for making the same

A martensitic stainless steel sheet which is hard to be softened by tempering caused by heating during the use of a disk brake, can maintain the predetermined hardness, and has excellent punching workability, bending workability before quenching, and a particularly small shear drop, and in which a predetermined hardness after quenching is constantly achieved, in a low carbon martensitic stainless steel sheet used only after quenching. Specifically, the sheet contains, on the basis of mass percent, 0.030% to 0.100% C; 0.50% or less of Si; 1.00% to 2.50% Mn; more than 10.00% to 15.00% Cr; at least one selected from the group consisting of 0.01% to 0.50% Ti, 0.01% to 0.50% V, 0.01% to 1.00% Nb, and 0.01% to 1.00% Zr; N in an amount defined by the following expression, N: 0.005% to (Ti+V)&#xd7;14/50+(Nb+Zr)&#xd7;14/90; and the balance being Fe and incidental impurities.

Low carbon martensitic stainless steel and method for production thereof

A ferritic stainless steel sheet for fuel tanks and fuel pipes comprises, by mass percent, about 0.1% or less of C; about 1.0% or less of Si; about 1.5% or less of Mn; about 0.06% or less of P; about 0.03% or less of S; about 1.0% or less of Al; about 11% to about 20% Cr; about 2.0% or less of Ni; about 0.5% to about 3.0% Mo; about 0.02% to about 1.0% V; about 0.04% or less of N; at least one of about 0.01% to about 0.8% Nb and about 0.01% to about 1.0% Ti; and the balance being Fe and incidental impurities. The ferritic stainless steel sheet is produced by rough-rolling a slab having the above composition; hot-rolling the rough-rolled sheet under a linear pressure of at least about 3.5 MN/m at a final pass in the finish rolling; cold-rolling the hot-rolled sheet at a gross reduction rate of at least about 75%; and annealing the cold-rolled sheet. The cold-rolling step includes one rolling stage or at least two rolling stages including intermediate annealing.

Ferritic stainless steel sheet for fuel tank and fuel pipe

The invention is a grain-oriented magnetic steel sheet having extremely low iron loss, suitable for use as an iron core material for transformers and power generators, and a method for producing the same. The method includes forming a coating layer on a surface of a steel sheet having a thickness of 0.27 mm or less by vapor deposition in a low oxidizing atmosphere with an oxygen partial pressure (Po ) of less than 0.1 atm and a total pressure of 0.1 atm or more. The steel sheet has extremely low iron loss with a thickness of 0.27 mm or less and includes a coating layer formed by vapor deposition on a matrix surface.

Grain oriented electromagnetic steel sheet exhibiting extremely small watt loss and method for producing the same

The soft Cr-containing steel includes, on a % by mass basis, C: from about 0.001% to about 0.020%, Si: more than about 0.10% and less than about 0.50%, Mn: less than about 2.00%, P: less than about 0.060%, S: less than about 0.008%, Cr: from about 12.0% to about 16.0%, Ni: from about 0.05% to about 1.00%, N: less than about 0.020%, Nb: from about 10&times;(C&plus;N) to about 1.00%, Mo: more than about 0.80% and less than about 3.00%, wherein the contents of alloying elements, represented by Si and Mo, respectively, on a % by mass, satisfy the formula Si &lE;1.2&minus;0.4 Mo, so as to prevent precipitation of the Laves phase and to stably secure an effect of increasing high-temperature strength due to solid solution Mo.

A ferritic stainless steel sheet for use in automobile fuel tanks and fuel pipes having smooth surface and resistance to organic acid is provided. The sheet contains, by mass, not more than about 0.1% C, not more than about 1.0 Si, not more than about 1.5 % Mn, not more than about 0.06% P, not more than about 0.03% S, about 11% to about 23% Cr, not more than about 2.0% Ni, about 0.5% to about 3.0% Mo, not more than about 1.0% Al, not more than about 0.04% N, at least one of not more than about 0.8% Nb and not more than about 1.0% Ti, and the balance being Fe and unavoidable impurities, satisfying the relationship: 18&lE;Nb/(C&plus;N)&plus;2Ti/(C&plus;N)&lE;60, wherein C, N, Nb, and. Ti in the relationship represent the C, N, Nb, and Ti contents by mass percent, respectively. A process for making the same is also provided.

Ferritic stainless steel sheet with excellent workability

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Chiba, Japan

Mineo Muraki