Global Patent Index - EP 2025770 A1

EP 2025770 A1 2009-02-18 - Ni-reduced austenite stainless steel

Title (en)

Ni-reduced austenite stainless steel

Title (de)

Austenitischer Edelstahl mit reduziertem Nickelanteil

Title (fr)

Acier inoxydable austénitique à teneur réduite en Ni

Publication

EP 2025770 A1 (EN)

Application

EP 08014087 A

Priority

JP 2007207482 A

Abstract (en)

Provided is an Ni-reduced austenite stainless steel having excellent recyclability with no problem of producibility depression to be caused by the surface property thereof and having good workability, season cracking resistance, corrosion resistance and stress corrosion cracking resistance in point of the material characteristics thereof. The steel comprises C in an amount of more than 0.05 % (by mass) and within a range of from 0.15 to 0.3 % as (C+N), Si in an amount of at most 1 %, Mn in an amount of from 0.5 to 2.5 %, Ni in an amount of from 3 to 6 %, Cr in an amount of from more than 16 to 25 % and Cu in an amount of from 0.8 to 4 %, and has Md30 of the following formula (1) of from -50 to 10 and SFE of the following formula (2) of at least 5: €ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ Md30 = 551-462(C+N)-9.2Si-8.1Mn-29(Ni+Cu)-13.7Cr€ƒ€ƒ€ƒ€ƒ€ƒ(1), €ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ SFE = 2.2Ni+6Cu-1.1Cr-13Si-1.2Mn+32€ƒ€ƒ€ƒ€ƒ€ƒ(2).

IPC 8 full level (invention and additional information)

C22C 38/00 (2006.01); C21D 8/02 (2006.01); C22C 38/02 (2006.01); C22C 38/42 (2006.01); C22C 38/58 (2006.01)

CPC (invention and additional information)

C22C 38/42 (2013.01); C22C 38/001 (2013.01); C22C 38/02 (2013.01); C22C 38/58 (2013.01)

Citation (applicant)

Citation (search report)

Designated contracting state (EPC)

DE FR GB

Designated extension state (EPC)

AL BA MK RS

EPO simple patent family

EP 2025770 A1 20090218; CN 101363103 A 20090211; JP 2009041072 A 20090226; JP 5014915 B2 20120829; KR 20090015817 A 20090212; TW 200923106 A 20090601; TW I394847 B 20130501; US 2009041613 A1 20090212

INPADOC legal status


2010-07-14 [18D] APPLICATION DEEMED TO BE WITHDRAWN

- Effective date: 20100112

2009-10-21 [AKX] PAYMENT OF DESIGNATION FEES

- Designated State(s): DE FR GB

2009-07-29 [17Q] FIRST EXAMINATION REPORT

- Effective date: 20090630

2009-06-03 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20090416

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 HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

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

- Countries: AL BA MK RS