Title:
ROLLED STEEL BAR OR WIRE FOR HOT FORGING
Document Type and Number:
WIPO Patent Application WO/2012/073896
Kind Code:
A1
Abstract:
A rolled steel bar or wire for hot forging capable of achieving at a high level both bending/surface-fatigue strength and machinability of components is provided. The rolled steel bar or wire for hot forging comprises, in % by mass, 0.1-0.25% C, 0.01-0.10% Si, 0.4-1.0% Mn, 0.003-0.05% S, 1.60-2.00% Cr, 0.10 % max. (including 0%) Mo, 0.025-0.05% Al, and 0.010-0.025% N. In formula (1), fn1 fulfills 1.82≦fn1≦2.10. P, Ti, and O in impurities are contained in the amounts of P at 0.025% max, Ti at 0.003% max, and O (oxygen) at 0.002% max. When 15 fields of view randomly selected in a cross-section so that each field of view has an area of 62,500 µm2 are examined, the maximum/minimum average ferrite particle diameter is 2.0 or less. fn1=Cr+2×Mo … (1).
Inventors:
DAITOH, Yoshihiro (1, Konomimachi, Kokurakita-ku, Kitakyushu-sh, Fukuoka 86, 〒8028686, JP)
大藤 善弘 (〒86 福岡県北九州市小倉北区許斐町１番地 株式会社住友金属小倉内 Fukuoka, 〒8028686, JP)
IMATAKA, Hideki (1, Konomimachi, Kokurakita-ku, Kitakyushu-sh, Fukuoka 86, 〒8028686, JP)
今高 秀樹 (〒86 福岡県北九州市小倉北区許斐町１番地 株式会社住友金属小倉内 Fukuoka, 〒8028686, JP)
大藤 善弘 (〒86 福岡県北九州市小倉北区許斐町１番地 株式会社住友金属小倉内 Fukuoka, 〒8028686, JP)
IMATAKA, Hideki (1, Konomimachi, Kokurakita-ku, Kitakyushu-sh, Fukuoka 86, 〒8028686, JP)
今高 秀樹 (〒86 福岡県北九州市小倉北区許斐町１番地 株式会社住友金属小倉内 Fukuoka, 〒8028686, JP)
Application Number:
JP2011/077407
Publication Date:
June 07, 2012
Filing Date:
November 28, 2011
Export Citation:
Assignee:
SUMITOMO METAL INDUSTRIES, LTD. (5-33, Kitahama 4-chome Chuo-ku, Osaka-sh, Osaka 41, 〒5410041, JP)
住友金属工業株式会社 (〒41 大阪府大阪市中央区北浜４丁目５番３３号 Osaka, 〒5410041, JP)
DAITOH, Yoshihiro (1, Konomimachi, Kokurakita-ku, Kitakyushu-sh, Fukuoka 86, 〒8028686, JP)
大藤 善弘 (〒86 福岡県北九州市小倉北区許斐町１番地 株式会社住友金属小倉内 Fukuoka, 〒8028686, JP)
IMATAKA, Hideki (1, Konomimachi, Kokurakita-ku, Kitakyushu-sh, Fukuoka 86, 〒8028686, JP)
住友金属工業株式会社 (〒41 大阪府大阪市中央区北浜４丁目５番３３号 Osaka, 〒5410041, JP)
DAITOH, Yoshihiro (1, Konomimachi, Kokurakita-ku, Kitakyushu-sh, Fukuoka 86, 〒8028686, JP)
大藤 善弘 (〒86 福岡県北九州市小倉北区許斐町１番地 株式会社住友金属小倉内 Fukuoka, 〒8028686, JP)
IMATAKA, Hideki (1, Konomimachi, Kokurakita-ku, Kitakyushu-sh, Fukuoka 86, 〒8028686, JP)
International Classes:
C22C38/28; C21D8/06
Attorney, Agent or Firm:
UEBA Hidetoshi et al. (Intelix International, Aqua Dojima West 4-16, Dojimahama 1-chome, Kita-ku, Osaka-sh, Osaka 04, 〒5300004, JP)
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