Global Patent Index - EP 1047799 A1

EP 1047799 A1 2000-11-02 - ULTRA-HIGH STRENGTH STEELS WITH EXCELLENT CRYOGENIC TEMPERATURE TOUGHNESS

Title (en)

ULTRA-HIGH STRENGTH STEELS WITH EXCELLENT CRYOGENIC TEMPERATURE TOUGHNESS

Title (de)

ULTRAHOCHFESTE STÄHLE MIT HERVORRAGENDER TIEFTEMPERATURZÄHIGKEIT

Title (fr)

ACIERS PRESENTANT UNE RESISTANCE EXTREMEMENT ELEVEE ET UNE TENACITE EXCELLENTE AUX TEMPERATURES CRYOGENIQUES

Publication

EP 1047799 A1 (EN)

Application

EP 98931363 A

Priority

  • US 9812702 W
  • US 6819497 P

Abstract (en)

[origin: WO9932672A1] An ultra-high strength, weldable, low alloy steel, containing less than 9 wt.% nickel, with excellent cryogenic temperature toughness in the base plate and in the heat affected zone (HAZ) when welded, having a tensile strength greater than 830 MPa (120 ksi) and a microstructure comprising predominantly fine-grained lath martensite and/or fine-grained lower bainite, is prepared by heating a steel slab comprising iron and some or all of the additives carbon, manganese, nickel, nitrogen, copper, chrominum, molybdenum, silicon, niobium, vanadium, titanium, aluminum, and boron; reducing the slab to form plate in one or more passes in a temperature range in which austenite recrystallizes; finish rolling the plate in one or more passes in a temperature range below the austenite recrystallization temperature and above the Ar3 transformation temperature; quenching the finish rolled plate (10''') to at a suitable Quench Stop temperature; stopping the quenching; and tempering the plate (10''') at a suitable temperature for a period of time sufficient to cause precipitation of hardening particles.

IPC 1-7 (main, further and additional classification)

C21D 8/02; C22C 38/06; C22C 38/08; C22C 38/12; C22C 38/14

IPC 8 full level (invention and additional information)

C21D 1/19 (2006.01); C21D 6/02 (2006.01); C21D 8/02 (2006.01); C22C 38/00 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/08 (2006.01); C22C 38/12 (2006.01); C22C 38/14 (2006.01); C22C 38/16 (2006.01); C22C 38/58 (2006.01)

CPC (invention and additional information)

C21D 1/19 (2013.01); C21D 6/02 (2013.01); C21D 8/0226 (2013.01); C22C 38/001 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/08 (2013.01); C22C 38/12 (2013.01); C22C 38/14 (2013.01); C22C 38/16 (2013.01); C21D 2211/002 (2013.01); C21D 2211/008 (2013.01)

Citation (search report)

See references of WO 9932672A1

Designated contracting state (EPC)

BE FR GR IE IT NL

EPO simple patent family

WO 9932672 A1 19990701; AR 013108 A1 20001213; AT A915498 A 20011215; AU 8151198 A 19990712; BG 104622 A 20010330; BR 9813630 A 20001017; CA 2316968 A1 19990701; CN 1282381 A 20010131; CO 5050267 A1 20010627; DE 19882879 T1 20010426; DK 200000936 A 20000616; EP 1047799 A1 20001102; FI 20001438 A 20000616; GB 0013632 D0 20000726; GB 2348887 A 20001018; HR P980346 A2 19990831; HU 0101125 A2 20010828; HU 0101125 A3 20011029; IL 136842 D0 20010614; JP 2001527155 A 20011225; KR 20010024757 A 20010326; NO 20003175 A 20000619; NO 20003175 D0 20000619; OA 11422 A 20040421; PE 93599 A1 19991012; PL 342646 A1 20010618; SE 0002245 D0 20000616; SE 0002245 L 20000616; SI 20278 A 20001231; SK 8682000 A3 20010118; TN SN98098 A1 20001229; TR 200001797 T2 20010723; TW 459052 B 20011011; ZA 9805325 B 19991220

INPADOC legal status


2001-05-09 [18W] APPLICATION WITHDRAWN

- Date of withdrawal: 20010315

2000-11-02 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20000630

2000-11-02 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): BE FR GR IE IT NL