Title:
CARBURIZED-STEEL-COMPONENT PRODUCTION METHOD, AND CARBURIZED STEEL COMPONENT
Document Type and Number:
WIPO Patent Application WO/2015/098106
Kind Code:
A1
Abstract:
Provided is a carburized-steel-component production method with which gas carburization properties of a steel component having a high Si content are improved, and with which a reduction in productivity can be inhibited. This production method is provided with a preliminary gas-carburization step, and a main gas-carburization step. In the preliminary gas-carburization step, a steel component having a chemical composition which includes, expressed in mass%, C, Si, Mn, and Cr, and which satisfies formula (1), namely 6.5<3.5[Si%]+[Mn%]+3[Cr%]≤18, is subjected to gas-carburization treatment for at least 10 minutes, but for less than 20 hours, at a carburization temperature (Tp) (in ˚C) satisfying formula (A), namely 800≤Tp< 163×1n(CP+0.6)-41×1n(3.5[Si%]+[Mn%]+3[Cr%])+950, CP being substituted for the carbon potential during carburization in the preliminary gas-carburization step. In the main gas-carburization step, gas-carburization treatment is performed using a carburization time period (tr) (in minutes) and a carburization temperature (Tr) (in ˚C) which satisfy formula (B), namely 4<13340/(Tr+273.15)-1n(tr)<7.
Inventors:
KOYAMA TATSUYA (JP)
KUBOTA MANABU (JP)
KUBOTA MANABU (JP)
Application Number:
PCT/JP2014/006442
Publication Date:
July 02, 2015
Filing Date:
December 24, 2014
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP (JP)
International Classes:
C22C38/00; C21D1/06; C21D9/00; C21D9/32; C21D9/40; C22C38/60; C23C8/22
Domestic Patent References:
| WO2011132722A1 | 2011-10-27 | |||
| WO2011114836A1 | 2011-09-22 | |||
| WO2012077705A1 | 2012-06-14 | |||
| WO2012077705A1 | 2012-06-14 |
Foreign References:
| JP2008179848A | 2008-08-07 | |||
| JP2008291298A | 2008-12-04 | |||
| JP2011184768A | 2011-09-22 | |||
| JP2009127095A | 2009-06-11 | |||
| JP2009249684A | 2009-10-29 | |||
| JP2013204645A | 2013-10-07 | |||
| JP2008280610A | 2008-11-20 | |||
| JPH02156063A | 1990-06-15 |
Other References:
"IRON AND STEEL", vol. 7, 1 June 1972, THE IRON AND STEEL INSTITUTE OF JAPAN, pages: 926
See also references of EP 3088550A4
See also references of EP 3088550A4
Attorney, Agent or Firm:
ASCEND IP LAW FIRM (JP)
アセンド patent business corporation (JP)
アセンド patent business corporation (JP)
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