Title:
HIGH STRENGTH HOT ROLLED STEEL SHEET EXCELLENT IN PROCESSABILITY AND WELD CHARACTERISTICS AND MANUFACTURING METHOD THEREFOR
Document Type and Number:
Japanese Patent JP2015063731
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a high strength hot rolled steel sheet excellent in processability and weld characteristics having strength of 500 N/mmclass or more for press worked automobile components and a manufacturing method therefor.SOLUTION: There is provided a high strength hot rolled steel sheet excellent in processability and weld characteristics containing, by mass%, C:0.03 to 0.35%, Si:0.01% to 2.0%, Mn:0.3% to 4.0%, P:0.001% to 0.10%, S:0.0005% to 0.05%, N:0.0005% to 0.010%, Al:0.01% to 2.0% and the balance Fe with inevitable impurities and having a crystal structure containing a bainite phase of over 10%, a ferrite phase of over 20% and a pearlitic phase of less than 10% by area friction and a coverage factor of the ferrite phase by the bainite phase of over 30%.
Inventors:
OKAMOTO TSUTOMU
TOYODA TAKESHI
TOYODA TAKESHI
Application Number:
JP2013198328A
Publication Date:
April 09, 2015
Filing Date:
September 25, 2013
Export Citation:
Assignee:
NIPPON STEEL & SUMITOMO METAL CORP
International Classes:
C22C38/00; C21D8/02; C21D9/46; C22C18/00; C22C38/60
Domestic Patent References:
| JPH05179346A | 1993-07-20 | |||
| JP2009007659A | 2009-01-15 | |||
| JPH06240356A | 1994-08-30 | |||
| JP2004204326A | 2004-07-22 |
Foreign References:
| WO2011148490A1 | 2011-12-01 | |||
| FR2748033A1 | 1997-10-31 |
Other References:
MING-HUI CAL、外４名: "Effects of Si on Microstructural Evolution and Mechanical Properties of Hot-rolled Ferrite and Baini", ISIJ INTERNATIONAL, vol. 51, no. 3, JPN6017007250, 2011, JP, pages 476 - 481, ISSN: 0003511654
Attorney, Agent or Firm:
Intellectual Property Office
Shunta Naito
Hisataka Tanaka
Katori Hideo
Shunta Naito
Hisataka Tanaka
Katori Hideo