Global Patent Index - EP 1644540 A2

EP 1644540 A2 20060412 - NANO-PRECIPITATION STRENGTHENED ULTRA-HIGH STRENGTH CORROSION RESISTANT STRUCTURAL STEELS

Title (en)

NANO-PRECIPITATION STRENGTHENED ULTRA-HIGH STRENGTH CORROSION RESISTANT STRUCTURAL STEELS

Title (de)

NANOAUSSCHEIDUNGSVERFESTIGTE ULTRAHOCHFESTE KORROSIONSBESTÄNDIGE BAUSTÄHLE

Title (fr)

ACIERS DE CONSTRUCTION ANTICORROSION A ULTRA-HAUTE RESISTANCE RENFORCE PAR NANO-PRECIPITATION

Publication

EP 1644540 A2 20060412 (EN)

Application

EP 04754496 A 20040604

Priority

  • US 2004017898 W 20040604
  • US 47600503 P 20030605
  • US 53385503 P 20031231
  • US 86018504 A 20040603

Abstract (en)

[origin: WO2004108970A2] A nanocarbide precipitation strengthened ultrahigh-strength, corrosion resistant, structural steel possesses a combination of strength and corrosion resistance comprising in combination, by weight, about: 0.1 to 0.5 % carbon (C), about 8 to 17 % cobalt (Co), 0 to about 10 % nickel (Ni), about 6 to 12 % chromium (Cr), less than about 1 % silicon (Si), less than about 0.5 % manganese (Mn), and less than about 0.15 % copper (Cu), with additives selected from the group comprising about: less than 3% molybdenum (Mo), less than 0.3 % niobium (Nb), less than 0.8 % vanadium (V), less than 0.2 % tantalum (Ta), less than 3 % tungsten (W), and combinations thereof, with additional additives selected from the group comprising about: less than 0.2 % titanium (Ti), less than 0.2 % lanthanum (La) or other rare earth elements, less than 0.15 % zirconium (Zr), less than 0.005 % boron (B), and combinations thereof, impurities of less than about: 0.02 % sulfur (S), 0.012 % phosphorus (P), 0.015 % oxygen (O) and 0.015 % nitrogen (N), the remainder substantially iron (Fe), incidental elements and other impurities. The alloy is strengthened by nanometer scale M2C carbides within a fine lath martensite matrix from which enhanced chemical partitioning of Cr to the surface provides a stable oxide passivating film for corrosion resistance. The alloy, with a UTS in excess of 280 ksi, is useful for applications such as aircraft landing gear, machinery and tools used in hostile environments, and other applications wherein ultrahigh-strength, corrosion resistant, structural steel alloys are desired.

IPC 1-7

C21B 3/00

IPC 8 full level

C21D 1/22 (2006.01); C21D 1/28 (2006.01); C21D 6/00 (2006.01); C21D 6/04 (2006.01); C21D 8/00 (2006.01); C21D 8/02 (2006.01); C21D 9/00 (2006.01); C22C 38/22 (2006.01); C22C 38/30 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); C22C 38/52 (2006.01)

IPC 8 main group level

C21B (2006.01)

CPC (source: EP)

C21D 1/22 (2013.01); C21D 1/28 (2013.01); C21D 6/001 (2013.01); C21D 6/002 (2013.01); C21D 6/007 (2013.01); C21D 6/04 (2013.01); C21D 8/021 (2013.01); C22C 38/44 (2013.01); C22C 38/46 (2013.01); C22C 38/52 (2013.01); C21D 2211/008 (2013.01)

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PL PT RO SE SI SK TR

DOCDB simple family (publication)

WO 2004108970 A2 20041216; WO 2004108970 A3 20060406; CA 2528165 A1 20041216; EP 1644540 A2 20060412; EP 1644540 A4 20060816; JP 2006526711 A 20061124

DOCDB simple family (application)

US 2004017898 W 20040604; CA 2528165 A 20040604; EP 04754496 A 20040604; JP 2006515231 A 20040604