Global Patent Index - EP 3168312 B1

EP 3168312 B1 20190410 - ENGINEERING STEEL WITH BAINITIC STRUCTURE, FORGED PART PRODUCED THEREFROM AND METHOD FOR MAKING A FORGED PART

Title (en)

ENGINEERING STEEL WITH BAINITIC STRUCTURE, FORGED PART PRODUCED THEREFROM AND METHOD FOR MAKING A FORGED PART

Title (de)

EDELBAUSTAHL MIT BAINITISCHEM GEFÜGE, DARAUS HERGESTELLTES SCHMIEDETEIL UND VERFAHREN ZUR HERSTELLUNG EINES SCHMIEDETEILS

Title (fr)

ACIER INOXYDABLE DE CONSTRUCTION COMPRENANT UN JOINT BAINITIQUE, PIÈCE FORGÉE AINSI FABRIQUÉE ET PROCÉDÉ DE FABRICATION D'UNE PIÈCE FORGÉE

Publication

EP 3168312 B1 20190410 (DE)

Application

EP 15194741 A 20151116

Priority

EP 15194741 A 20151116

Abstract (en)

[origin: CA3005378A1] The invention provides a steel, which has a high strength, without complex heat treatment processes having to be performed for this purpose, and at the same time has a low tendency to warp. For this purpose, the high-grade structural steel according to the invention consists of (in % by weight) up to 0.25% C, up to 0.45% Si, 0.20 - 2.00% Mn; up to 4.00% Cr, 0.6 - 3.0% Mo, 0.004 - 0.020% N, up to 0.40% S, 0.001 - 0.035% Al, 0.0005 - 0.0025% B, up to 0.015% Nb, up to 0.01% Ti, up to 0.10% V, up to 1.5% Ni and up to 2.0% Cu, the remainder iron and unavoidable impurities, wherein the Al content %Al, the Nb content %Nb, the Ti content %Ti, the V content %V and the N content %N of the high-grade structural steel respectively meet the following condition: %Al/27 + %Nb/45 + %Ti/48 + %V/25 > %N/3.75. The high-grade structural steel according to the invention has a yield strength of at least 750 MPa, a tensile strength of at least 950 MPa and a microstructure which consists at least 80% by volume of bainite and in total at most 20% by volume of residual austenite, ferrite, pearlite and/or martensite. On account of its combination of properties, the steel according to the invention is suitable in particular for the production of forged parts with great changes in cross section over its length. The invention also discloses a method for producing such forged components.

IPC 8 full level

C21D 1/02 (2006.01); C21D 1/20 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/12 (2006.01); C22C 38/18 (2006.01); C22C 38/22 (2006.01); C22C 38/38 (2006.01)

CPC (source: EP KR RU US)

C21D 1/02 (2013.01 - EP KR US); C21D 1/20 (2013.01 - EP KR US); C21D 7/13 (2013.01 - KR); C21D 8/00 (2013.01 - RU); C22C 38/001 (2013.01 - EP KR US); C22C 38/02 (2013.01 - EP US); C22C 38/04 (2013.01 - EP KR US); C22C 38/06 (2013.01 - EP KR US); C22C 38/12 (2013.01 - KR); C22C 38/14 (2013.01 - KR); C22C 38/42 (2013.01 - EP US); C22C 38/44 (2013.01 - EP US); C22C 38/46 (2013.01 - EP US); C22C 38/48 (2013.01 - EP US); C22C 38/50 (2013.01 - EP US); C22C 38/54 (2013.01 - EP US); C22C 38/58 (2013.01 - RU); C21D 7/13 (2013.01 - EP US); C21D 2211/002 (2013.01 - EP KR US); C21D 2211/008 (2013.01 - EP KR US)

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

DOCDB simple family (publication)

EP 3168312 A1 20170517; EP 3168312 B1 20190410; CA 3005378 A1 20170526; CA 3005378 C 20200714; CN 108474049 A 20180831; CN 108474049 B 20210108; DK 3168312 T3 20190701; ES 2733805 T3 20191203; JP 2019501280 A 20190117; JP 6616501 B2 20191204; KR 102178736 B1 20201113; KR 20180071357 A 20180627; PL 3168312 T3 20190930; PT 3168312 T 20190716; RU 2703085 C1 20191015; US 2018327873 A1 20181115; WO 2017085072 A1 20170526

DOCDB simple family (application)

EP 15194741 A 20151116; CA 3005378 A 20161115; CN 201680069274 A 20161115; DK 15194741 T 20151116; EP 2016077761 W 20161115; ES 15194741 T 20151116; JP 2018521262 A 20161115; KR 20187014749 A 20161115; PL 15194741 T 20151116; PT 15194741 T 20151116; RU 2018121935 A 20161115; US 201615773745 A 20161115