Global Patent Index - EP 2025769 A1

EP 2025769 A1 2009-02-18 - HIGH-DUCTILITY HIGH-CARBON STEEL WIRE

Title (en)

HIGH-DUCTILITY HIGH-CARBON STEEL WIRE

Title (de)

STARK DEHNBARER HARTSTAHLDRAHT

Title (fr)

FIL D'ACIER À TENEUR ÉLEVÉE EN CARBONE ET DE GRANDE DUCTILITÉ

Publication

EP 2025769 A1 (EN)

Application

EP 07744836 A

Priority

  • JP 2007061497 W
  • JP 2006153303 A

Abstract (en)

A high-carbon steel wire rod of high ductility for steel cord and the like is provided that experiences little breakage during drawing. The high-carbon steel wire rod of high ductility is a high-carbon steel wire rod fabricated by hot rolling that that has a carbon content of 0.7 mass% or greater, wherein 95% or greater of the wire rod metallographic structure is pearlite structure and the maximum pearlite block size of pearlite at the core of the hot-rolled wire rod is 65 µm or less. The high-carbon steel wire rod of high ductility has a tensile strength in a range of {248 + 980 x (C mass%)} ± 40 MPa} and a reduction of area of {72.8 - 40 x (C mass%) %} or greater. The high-carbon steel wire rod of high ductility is characterized in that the average pearlite block size at the core of the hot-rolled wire rod constituted by ferrite grain boundaries of an orientation difference of 9 degrees or greater as measured with an EBSP analyzer is 10 µm or greater and 30 µm or less.

IPC 8 full level (invention and additional information)

C22C 38/00 (2006.01); B21B 3/00 (2006.01); C22C 38/04 (2006.01); C22C 38/54 (2006.01)

CPC (invention and additional information)

C22C 38/02 (2013.01); C21D 8/065 (2013.01); C22C 38/002 (2013.01); C22C 38/04 (2013.01); C22C 38/18 (2013.01); D07B 1/066 (2013.01); B21B 1/16 (2013.01)

Designated contracting state (EPC)

BE DE FR GB IT LU

Designated extension state (EPC)

AL BA HR MK RS

EPO simple patent family

EP 2025769 A1 20090218; EP 2025769 A4 20100818; BR PI0702892 A2 20110315; BR PI0702892 B1 20141118; CA 2617381 A1 20071206; CA 2617381 C 20130917; CN 101341270 A 20090107; CN 101341270 B 20120418; JP 5092749 B2 20121205; JP WO2007139234 A1 20091015; KR 101018054 B1 20110302; KR 20080017433 A 20080226; US 2009087336 A1 20090402; US 2011284139 A1 20111124; WO 2007139234 A1 20071206

INPADOC legal status


2014-06-11 [18D] APPLICATION DEEMED TO BE WITHDRAWN

- Effective date: 20131231

2013-01-23 [RAP1] TRANSFER OF RIGHTS OF AN APPLICATION

- Owner name: NIPPON STEEL & SUMITOMO METAL CORPORATION

2012-01-25 [17Q] FIRST EXAMINATION REPORT

- Effective date: 20111121

2010-08-18 [A4] DESPATCH OF SUPPLEMENTARY SEARCH REPORT

- Effective date: 20100721

2009-07-29 [DAX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT (TO ANY COUNTRY) (DELETED)

2009-07-29 [RBV] DESIGNATED CONTRACTING STATES (CORRECTION)

- Designated State(s): BE DE FR GB IT LU

2009-02-18 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20080221

2009-02-18 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR

2009-02-18 [AX] REQUEST FOR EXTENSION OF THE EUROPEAN PATENT TO:

- Countries: AL BA HR MK RS