Title:
強度延性バランス、めっき密着性と耐食性に優れた高張力溶融亜鉛めっき鋼板および高張力合金化溶融亜鉛めっき鋼板
Document Type and Number:
Japanese Patent JP4631241
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a high tensile hot dip galvanizing or galvannealed steel sheet which has excellent adhesion for galvanizing even when a base steel sheet largely containing Si and Mn, has excellent mechanical properties such as press formability and an excellent balance in strength and ductility, and has excellent corrosion resistance. SOLUTION: The surface of a steel sheet having a composition containing, by mass, 0.05 to 0.25% C, >0.50 to <2.00% Si, <=3.5% Mn, and 0.01 to 1.0% Al, and in which the mass ratio of Mn/Si in the steel is 0.5 to <2, and having a composite structure consisting of tempered martensite, retained austenite, ferrite, and a low temperature transformed phase, and in which the volume fraction of the tempered martensite is >=20%, and the volume fraction of the retained austenite is >=2% is provided with a galvanized layer in which the concentration of Al and the concentration of Si in the plated layer satisfy the Mn/Si concentration in the steel, and a specified relational equation, and, further, the content of oxygen in the surface layer of ferrite after the removal of the plated layer is controlled to >=0.05 g/m<2> .
Inventors:
Yoshitsugu Suzuki
Kyono Kazuaki
Kyono Kazuaki
Application Number:
JP2001288740A
Publication Date:
February 16, 2011
Filing Date:
September 21, 2001
Export Citation:
Assignee:
jfe Steel Corporation
International Classes:
C22C38/00; C23C2/06; C22C18/00; C22C18/04; C22C38/06; C22C38/58; C23C2/40
Domestic Patent References:
| JP2002235160A |
Attorney, Agent or Firm:
Nozomi Watanabe
Haruko Sanwa
Haruko Sanwa