586 patents
Page 7 of 30
Utility
Hot-rolled steel sheet and manufacturing method thereof
28 Dec 21
There is provided a hot-rolled steel sheet in which a composition contains: 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; O: 0.01% or less; Ti: 0.01 to 0.30%; and the balance being composed of iron and impurities and a structure is composed of by volume fraction, 90% or more of tempered martensite with an average aspect ratio of 2 or less, or 90% or more in total of both tempered martensite and lower bainite.
Akifumi Sakakibara, Tatsuo Yokoi, Hiroshi Shuto, Yuuki Kanzawa, Masafumi Azuma
Filed: 31 Jan 19
Utility
Nickel-containing steel for low temperature service and low-temperature tank
28 Dec 21
A nickel-containing steel for low temperature service having a determined chemical composition of a Ni content of from 5.0 to 8.0%, in which the volume fraction of retained austenite in a region of 1.5 mm from a surface in the thickness direction is from 3.0 to 20.0% by volume, and the ratio of the hardness in a region of 1.0 mm from a surface in the thickness direction to the hardness in a region of ¼ of the thickness from a surface in the thickness direction is 1.1 or less, and a low-temperature tank using the nickel-containing steel for low temperature service.
Kazuyuki Kashima, Takayuki Kagaya
Filed: 30 Nov 17
Utility
High-strength cold-rolled steel sheet
28 Dec 21
A high-strength cold-rolled steel sheet which is a steel sheet having a tensile strength of 980 MPa or more has a predetermined chemical component composition, a metallographic microstructure of the steel sheet contains, by area ratio, ferrite and granular bainite: 10% or more and 50% or less in total, one or both of upper bainite and lower bainite: 10% or more and 50% or less in total, tempered martensite: more than 0% and 30% or less, retained austenite: 5% or more, and one or more of pearlite, cementite, and martensite: 0% to 10% in total, and an area ratio of the ferrite with respect to a total area ratio of the ferrite and the granular bainite is 25% or less.
Yuri Toda, Kunio Hayashi, Katsuya Nakano, Eisaku Sakurada, Akihiro Uenishi, Kengo Takeda
Filed: 15 Nov 17
Utility
Nickel-containing steel plate for use at low temperature and tank for use at low temperature using the same
21 Dec 21
A nickel-containing steel plate for use at a low temperature, having a predetermined chemical composition, in which the volume fraction of retained austenite at a position 1.5 mm from the surface of the steel plate in the thickness direction is from 3.0 to 20.0% by volume; in which the maximum distance between adjacent grains of retained austenite on prior austenite grain boundaries at the position 1.5 mm from the surface of the steel plate in the thickness direction is 12.5 μm or less; and in which the circle equivalent diameter of grains of retained austenite at a position corresponding to ¼ of the plate thickness from the surface of the steel plate in the thickness direction is 2.5 μm or less.
Takayuki Kagaya, Kazuyuki Kashima
Filed: 31 Oct 17
Utility
Steel pipe for fuel injection pipe and method for producing the same
21 Dec 21
A steel pipe for fuel injection pipe has a tensile strength of 500 to 900 MPa and a yield ratio of 0.50 to 0.85, and has a critical internal pressure (IP) satisfying [IP≥0.41×TS×α] (α=[(D/d)2−1]/[0.776×(D/d)2], where TS: tensile strength (MPa) of the steel pipe, D: steel pipe outer diameter (mm), and d: steel pipe inner diameter (mm)), wherein a circumferential-direction residual stress on an inner surface of the pipe is −20 MPa or lower after the steel pipe is split in half in a pipe axis direction.
Tatsuya Masuda, Tsugumi Yamazaki, Hiroaki Kondo, Taizo Makino, Masahiro Yamazaki, Katsunori Nagao
Filed: 26 May 16
Utility
Steel wire and wire rod
21 Dec 21
A predetermined composition is had, when a C content is represented by (C %), in a case of (C %) being not less than 0.35% nor more than 0.65%, a volume fraction of pearlite is 64×(C %)+52% or more, and in a case of (C %) being greater than 0.65% and 0.85% or less, the volume fraction of pearlite is not less than 94% nor more than 100%, and a structure of the other portion is composed of one or two of proeutectoid ferrite and bainite.
Makoto Okonogi, Shingo Yamasaki, Akifumi Kawana, Hideaki Gotohda
Filed: 27 Mar 20
Utility
Hot rolled steel sheet and method for producing same
14 Dec 21
Provided is a hot rolled steel sheet comprising a predetermined composition wherein the hot rolled steel sheet comprises a dual structure of, by area fraction, a structural fraction of a martensite phase of 10 to 40% and a structural fraction of a ferrite phase of 60% or more, has an average grain size of ferrite grains of 5.0 μm or less, and has a coverage rate of martensite grains by ferrite grains of more than 60%.
Takeshi Toyoda, Tetsuya Hirashima, Riki Okamoto
Filed: 30 Oct 18
Utility
Shape inspection apparatus and shape inspection method
14 Dec 21
A shape inspection apparatus includes N illumination light sources, a line sensor camera, a measurement control unit, and a data processing unit.
Yusuke Konno, Takayuki Sonoda, Nobuhiro Furuya
Filed: 7 Dec 18
Utility
Austenitic stainless steel plate
14 Dec 21
There is provided a precipitation-strengthened stainless steel plate having a chemical composition: by mass %, C: 0.01 to 0.10%; Si: 0.02 to 3.0%; Mn: 0.02 to 2.0%; Ni: 20 to 30%, Cr: 14 to 25.0%; Mo: 1.0 to 4.0%; Cu: 0.01 to 2.0%; Co: 0.01 to 0.5%; V: 0.1 to 1.0%; B: 0.001 to 0.01%; N: 0.02% or less; Ti: 2.0 to 5.0%; Al: 0.002 to 5.0%; Ti+Al: 3.3 to 6.0%; and the balance being Fe and impurities, the precipitation-strengthened stainless steel plate having a Vickers hardness Hv of 300 or higher, wherein the number density γ′: Ni3(Al, Ti), which is an intermetallic compound, is 0 to 5/μm2.
Masayoshi Sawada, Yuichi Fukumura
Filed: 15 Sep 15
Utility
Raw material for direct reduction, method of producing raw material for direct reduction, and method of producing reduced iron
14 Dec 21
A raw material for direct reduction which is reduced in a shaft furnace includes a raw material, and a coating layer which coats the raw material and has a porosity of 20 volume % or more.
Moritoshi Mizutani, Tsunehisa Nishimura
Filed: 30 Mar 20
Utility
Side sealing device, twin-roll continuous casting apparatus, and method of manufacturing cast strip
7 Dec 21
A side sealing device for a twin-roll continuous casting apparatus, which supplies molten metal to a molten metal pool portion formed by a pair of rotating mold rolls and a pair of side weirs through an immersion nozzle and causes solidified shells to be formed and to grow on peripheral surfaces of the mold rolls to manufacture a cast strip, seals end surface sides of the mold rolls by each side weir.
Masafumi Miyazaki, Takashi Arai, Kazuya Maruyama, Shuji Wakida, Naoki Kamachi, Masanobu Hayama
Filed: 8 May 18
Utility
Cross angle identification method, cross angle identification device, and rolling mill
7 Dec 21
The present invention provides a method for identifying an inter-roll cross angle in a rolling mill of four-high or more including at least a pair of work rolls and a pair of backup rolls by, when rolling is not performed, applying a roll bending force to apply a load between rolls of an upper roll assembly including the work roll on the upper side and between rolls of a lower roll assembly including the work roll on the lower side, in a state where a roll gap between the work rolls is put into an open state, detecting vertical roll loads that act in the vertical direction on the rolling support positions on the working side and the driving side of at least one of the backup roll on the upper side or the backup roll on the lower side, and calculating a load difference between the vertical roll loads on the working side and the driving side.
Atsushi Ishii, Shota Ishitsuka, Yuuto Okabe, Daisuke Nikkuni
Filed: 28 Feb 18
Utility
Hole widening method, forming tool, and formed product
7 Dec 21
There is provided a hole widening method including a preparing process of preparing a forming tool which has a diameter-increasing portion increasing in diameter from a front end side toward a rear end side and a line-shaped projection formed to protrude outward from a surface of the diameter-increasing portion, and a workpiece in which a pilot hole is formed; and a hole widening process of successively widening the pilot hole by pushing the forming tool into the pilot hole such that the line-shaped projection of the forming tool comes into point contact with a part of a circumferential edge portion of the pilot hole in the workpiece two times or more, and forming a stretched flange.
Jun Nitta, Shigeru Yonemura, Satoshi Shirakami, Takashi Yasutomi
Filed: 2 Sep 16
Utility
Device and method of detecting magnetic characteristic change for long material
7 Dec 21
A device of detecting magnetic characteristic change for a long material includes: an exciting coil into which the long material is inserted and which magnetizes the long material in a longitudinal direction; a detecting coil into which the long material is inserted and which detects a magnetic flux generated in the long material due to magnetization by the exciting coil; and a yoke member which has a first opening portion which is positioned on one side of the long material in the longitudinal direction and into which the long material is inserted and a second opening portion which is positioned on the other side of the long material in the longitudinal direction and into which the long material is inserted, and has a shape which is substantially axially symmetrical about an axis passing the first opening portion and the second opening portion, and the exciting coil and the detecting coil are surrounded by the yoke member, the first opening portion, and the second opening portion.
Toshiyuki Suzuma, Yoshiyuki Nakao, Yoshiyuki Ota
Filed: 29 Jun 18
Utility
Grain-oriented electrical steel sheet
30 Nov 21
A grain-oriented electrical steel sheet includes: a steel sheet; and an amorphous oxide layer that is formed on the steel sheet, in which a glossiness of a surface is 150% or higher.
Shinsuke Takatani, Yoshiyuki Ushigami, Hiroyasu Fujii, Shuichi Nakamura, Takeshi Imai
Filed: 13 Jul 18
Utility
Grain-oriented electrical steel sheet and method for producing same
30 Nov 21
A grain-oriented electrical steel sheet includes: a base steel sheet; an intermediate layer arranged in contact with the base steel sheet; and an insulation coating arranged in contact with the intermediate layer to be an outermost surface, in which a Cr content of the insulation coating is 0.1 at % or more on average, and when viewing a cross section whose cutting direction is parallel to a thickness direction, the insulation coating has a compound layer containing a crystalline phosphide in an area in contact with the intermediate layer.
Shinji Yamamoto, Yoshiyuki Ushigami
Filed: 13 Jul 18
Utility
Steel sheet
23 Nov 21
A steel sheet has a predetermined chemical composition, and a surface exhibits an absorption peak at which a reflectance is not less than 50% nor more than 85% in a range of wave numbers of 1200 cm−1 to 1300 cm−1 by a Fourier transform-infrared spectroscopy analysis by a reflection absorption spectrometry method, and does not exhibit an absorption peak in a range of wave numbers of 1000 cm−1 to 1100 cm−1, or exhibits an absorption peak at which a reflectance is 85% or more in the range of wave numbers of 1000 cm−1 to 1100 cm−1, wherein Ni of 3 mg/m2 to 100 mg/m2 adheres to the surface.
Kohei Ueda, Hiroyuki Kawata, Takayuki Kitazawa, Takeshi Yasui, Hiroyuki Ban
Filed: 25 Sep 15
Utility
Hot stamped article
23 Nov 21
A hot stamped article of high strength steel sheet excellent in bending deformability having a predetermined chemical composition, having an area rate of 90% or more of the microstructures of the steel sheet comprised of one or more of lower bainite, martensite, and tempered martensite, and having a ratio of the length of grain boundaries with a rotational angle about a rotational axis of the <011> direction of the crystal grains of the lower bainite, martensite, and tempered martensite of 15° or more with respect to the length of grain boundaries with a rotational angle of 5° to 75° of 80% or more.
Yuri Toda, Kazuo Hikida, Shingo Fujinaka, Tomohito Tanaka
Filed: 29 Mar 18
Utility
Steel bar for hot forging
23 Nov 21
Yusuke Miyakoshi, Motoki Takasuga
Filed: 23 Feb 18
Utility
Hot stamped article
23 Nov 21
A hot stamped article excellent in strength having a predetermined composition, having an average crystal grain size of prior austenite of 3 μm or less, containing at least one of lower bainite, martensite, and tempered martensite in an area rate of 90% or more, and having a grain boundary solid solution ratio Z, defined by Z=(mass % of one or both of Nb and Mo at the grain boundaries)/(mass % of one or more of Nb and Mo at time of dissolution) of 0.3 or more.
Yuri Toda, Kazuo Hikida, Shingo Fujinaka, Tomohito Tanaka
Filed: 29 Mar 18