Title:
【発明の名称】優れた極低温靭性をもつ超高強度三重相鋼
Document Type and Number:
Japanese Patent JP2002533567
Kind Code:
A
Abstract:
An ultra-high strength, weldable, low alloy, triple phase steel with excellent cryogenic temperature toughness in the base plate and in the heat affected zone (HAZ) when welded, having a tensile strength greater than about 830 MPa (120 ksi) and a microstructure comprising a ferrite phase, a second phase of predominantly lath martensite and lower bainite, and a retained austenite phase, is prepared by heating a steel slab comprising iron and specified weight percentages of some or all of the additives carbon, manganese, nickel, nitrogen, copper, chromium, 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; further reducing the plate in one or more passes in a temperature range below the austenite recrystallization temperature and above the Ar3 transformation temperature; finish rolling the plate between the Ar3 transformation temperature and the Ar1 transformation temperature; quenching the finish rolled plate to a suitable Quench Stop Temperature (QST); and stopping the quenching.
Inventors:
Kuja Young
Bangal Narasimha-Lao Vee
Aya Raghavan
Vaughn Glenn A
Bangal Narasimha-Lao Vee
Aya Raghavan
Vaughn Glenn A
Application Number:
JP2000589742A
Publication Date:
October 08, 2002
Filing Date:
December 16, 1999
Export Citation:
Assignee:
Exxon Mobil Upstream Research Company
International Classes:
C21D1/02; C21D1/19; C21D8/02; C22C38/00; C22C38/04; C22C38/06; C22C38/08; C22C38/12; C22C38/14; C22C38/58; (IPC1-7): C21D8/02; C22C38/00; C22C38/14; C22C38/58
Attorney, Agent or Firm:
Minoru Nakamura (9 outside)