公开(公告)号：US20180251876A1

公开(公告)日：2018-09-06

申请号：US15754364

申请日：2016-08-12

申请人： Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.)

发明人： Yuki SASAKI ,  Takuya KOCHI ,  Masamichi CHIBA ,  Masayuki SAKATA ,  Shogo MURAKAMI

IPC分类号： C22C38/60 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C22C38/14 ,  C21D8/06

CPC分类号： C22C38/60 ,  C21D1/18 ,  C21D1/32 ,  C21D8/06 ,  C21D8/065 ,  C21D2211/005 ,  C21D2211/009 ,  C21D2261/00 ,  C22C38/00 ,  C22C38/001 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/14

摘要： Disclosed herein is a mechanical structure steel for cold-working that includes C, Si, Mn, P, S, Al, and N and has a metal microstructure including proeutectoid ferrite and pearlite, in which a total area ratio of the proeutectoid ferrite and the pearlite with respect to the entire microstructure is 90% or more, while an area ratio Af of the proeutectoid ferrite with respect to the entire microstructure satisfies a relationship of Af≥A where an A value is represented by formula (1) below, an average circle equivalent diameter of a bcc-Fe crystal grain is in a range of 15 to 30 μm, and a pearlite lamellar spacing is 0.20 μm or less on average: A=(103−128×[C(%)])×0.80(%)  (1) where [C (%)] in the formula (1) indicates the C content in percent by mass.

公开(公告)号：US20180105894A1

公开(公告)日：2018-04-19

申请号：US15562631

申请日：2016-03-16

申请人： Kabushiki Kaisha Kobe Seiko Sho {Kobe Steel, Ltd.)

发明人： Yuki SASAKI ,  Takuya KOCHI ,  Masamichi CHIBA ,  Masayuki SAKATA

IPC分类号： C21D9/52 ,  C22C38/40 ,  C22C38/32 ,  C22C38/20 ,  C22C38/12 ,  C22C38/08 ,  C22C38/18 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C22C38/00 ,  C21D1/32 ,  C21D8/06 ,  C21D6/00

CPC分类号： C21D9/525 ,  C21D1/32 ,  C21D6/002 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C21D8/06 ,  C21D8/065 ,  C21D2211/003 ,  C21D2211/005 ,  C22C38/00 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/18 ,  C22C38/20 ,  C22C38/32 ,  C22C38/40 ,  C22C38/60

摘要： An object of the present invention is to provide a steel wire for mechanical structural parts that is reduced in deformation resistance and improved in crack resistance during cold working, and thus exhibits excellent cold workability. The steel wire for mechanical structural parts of the present invention is a steel wire containing, in mass %, 0.3 to 0.6% of C, (105 to 0.5% of Si, 0.2 to 1.7% of Mn, more than 0% and 0.03% or less of P, 0.001 to 0.05% of S, 0.005 to 0.1% of Al, and 0 to 0.015% of N, the balance being iron and inevitable impurities, wherein steel of the steel wire has a metal structure formed of ferrite and cementite, and the number proportion of cementite particles present in ferrite grain boundaries is 40% or more based on the total number of cementite particles.

公开(公告)号：US20170130295A1

公开(公告)日：2017-05-11

申请号：US15319115

申请日：2015-06-08

申请人： KABUSHIKI KAISHA KOBE SEIKO SHO (KOBE STEEL, LTD.)

发明人： Yuki SASAKI ,  Takehiro TSUCHIDA ,  Takuya KOCHI ,  Koji YAMASHITA ,  Masamichi CHIBA ,  Kei MASUMOTO ,  Masayuki SAKATA

IPC分类号： C21D9/52 ,  C21D8/06 ,  C21D6/00 ,  C22C38/20 ,  C22C38/00 ,  C22C38/08 ,  C22C38/12 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  B21B1/22 ,  C22C38/16

CPC分类号： C21D9/525 ,  B21B1/22 ,  B21B2001/225 ,  C21D6/002 ,  C21D6/005 ,  C21D6/008 ,  C21D8/06 ,  C21D8/065 ,  C21D2211/005 ,  C21D2211/009 ,  C22C38/001 ,  C22C38/002 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/16 ,  C22C38/18 ,  C22C38/20

摘要： Provided is a steel for a mechanical structure for cold working, which contains C, Si, Mn, P, S, Al and N and in which the metal structure includes pearlite and ferrite, the total areal proportion of pearlite and ferrite relative to the overall structure is 90% or higher, the average circle-equivalent diameter of bcc-Fe crystal grains surrounded by large angle grain boundaries is 5-15 μm, the average aspect ratio of pro-eutectoid ferrite crystal grains is 3.0 or lower, and the average spacing at the narrowest pearlite lamellar spacing is 0.20 μm or less.