Global Patent Index - EP 4079906 A1

EP 4079906 A1 20221026 - STRUCTURAL STEEL MATERIAL AND METHOD FOR MANUFACTURING SAME

Title (en)

STRUCTURAL STEEL MATERIAL AND METHOD FOR MANUFACTURING SAME

Title (de)

BAUSTAHLMATERIAL UND VERFAHREN ZU SEINER HERSTELLUNG

Title (fr)

MATÉRIAU D'ACIER STRUCTURAL ET PROCÉDÉ DE FABRICATION D'UN TEL MATÉRIAU

Publication

EP 4079906 A1 20221026 (EN)

Application

EP 20904167 A 20201215

Priority

  • KR 20190167594 A 20191216
  • KR 2020018361 W 20201215

Abstract (en)

A structural steel material according to an aspect of the present invention contains, in weight percent, 0.12-0.18% of C, 0.02-0.5% of Si, 0.6-1.6% of Mn, 0.002-0.06% of Sol. Al, 0.001-0.05% of Nb, 0.001-0.06% of V, 0.003-0.009% of Ti, 0.0002-0.006% of Ca, 0.0002-0.0005% of B, 0.001-0.006% of N, 0.02% or less of P, and 0.003% or less of S, with the remainder comprising Fe and inevitable impurities, and satisfies relational expression 1 below. The microstructure of the structural steel material includes a composite structure in which ferrite is the main phase and pearlite is the second phase, with the remainder comprising a hard structure, wherein the average grain size of the ferrite may be 20 µm or less. [Relational expression 1] [N] - 0.3*[Ti] - 0.1*[Nb] ≤ 0.001(wt%), where [N], [Ti], and [Nb] represent the contents (wt%) of N, Ti, and Nb in the steel material, respectively.

IPC 8 full level

C22C 38/04 (2006.01); C21D 8/02 (2006.01); C22C 38/02 (2006.01); C22C 38/12 (2006.01)

CPC (source: EP KR)

C21D 1/26 (2013.01 - EP); C21D 8/0205 (2013.01 - EP); C21D 8/0226 (2013.01 - EP KR); C21D 8/0263 (2013.01 - EP); C21D 8/0273 (2013.01 - KR); C21D 9/46 (2013.01 - EP); C22C 38/001 (2013.01 - EP); C22C 38/002 (2013.01 - EP); C22C 38/02 (2013.01 - EP KR); C22C 38/04 (2013.01 - EP KR); C22C 38/12 (2013.01 - EP KR); C21D 2211/005 (2013.01 - EP KR); C21D 2211/009 (2013.01 - EP)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

Designated extension state (EPC)

BA ME

Designated validation state (EPC)

KH MA MD TN

DOCDB simple family (publication)

EP 4079906 A1 20221026; CN 114729434 A 20220708; JP 2023507946 A 20230228; JP 7395750 B2 20231211; KR 102255828 B1 20210525; WO 2021125748 A1 20210624

DOCDB simple family (application)

EP 20904167 A 20201215; CN 202080083391 A 20201215; JP 2022536892 A 20201215; KR 20190167594 A 20191216; KR 2020018361 W 20201215