TH149987A - Cold rolled steel sheet, hot dipped galvanized And processes for the production of steel sheets - Google Patents

Abstract

DC60 (29/06/60) in high strength hot dip galvanized cold rolled steel sheet where it is excellent in ductility, hardenability with action. And the ability to make a face With stretching and where it will have a tensile strength of 750 MPa or higher, the base metal cold-rolled steel plate will have Chemical mixtures in% by mass containing C: greater than 0.10% and less than 0.25%, Si: greater than 0.50% and less than 2.0%, and Mn: greater than 1.50% and 3.0% or less. One or more species of Ti, Nb, V, Cr, Mo, B, Ca, Mg, REM, and Bi, P: less than 0.050%, Si: 0.010% or less, sol.Al <ul>.50% or less. And N: 0.010% or less and a metallurgical structure where the primary phase is a Deformed at low temperature and the second phase has a preserved austenite. The preserved Austenite will The volume ratio was greater than 4.0% and less than 25.0% compared to the overall structure and the average grain size of less than 0.80 μm. A preserved austenite with a grain size of 1.2 μm or more would be 3.0 X 10 to the power of -2 / square μm or less:

Claims (1)

: DC60 (29/06/60) in high strength hot dip galvanized cold rolled steel sheet where it is excellent in ductility, hardenability with action. And the ability to make a face Flange with elongation and where it will have a tensile strength of 750 MPa or higher, the substrate cold-rolled steel sheet will contain: chemical mixture in% by mass containing C: greater. 0.10% and less than 0.25%, Si: greater than 0.50% and less than 2.0% and Mn: greater than 1.50% and 3.0% or less, and, as an alternative to one or more of Ti, Nb, V, Cr, Mo, B, Ca, Mg, REM and Bi, P: less than 0.050%, Si: 0.010% or less, so l.Al <ul>.50% or less, and N: 0.010% or less and metallurgical structure. Where the primary phase is the product Deformed at low temperature and the second phase has a preserved austenite. The preserved Austenite will The volume ratio was greater than 4.0% and less than 25.0% compared to the overall structure and the average grain size of less than 0.80 μm. And in preserved austenite, density by number of A retained austenite with a grain size of 1.2 μm or more would be 3.0 X 10 to the power of -2 / square μm or less. The claim (Section 1) appears on the advertisement page: Edit 29 Jun 2017 1.Cold rolled steel sheet, hot dipped galvanized with a layer of hot dipped galvanized on the surface of the sheet. Cold-rolled steel, characterized by the presence of chemical mixtures included in% by mass, C: greater than 0.10% and less than 0.25%, Si: greater than 0.50% and less than 2.0%, Mn. : Greater than 1.50% and at most 3.0%, P: less than 0.050%, S: at most 0.010%, so l. Al: at least 0%.