TH177161A - High-strength steel plates and manufacturing methods for them, as well as Manufacturing method for high-strength galvanized sheet steel - Google Patents

Abstract

The invention discloses a high strength steel plate with a tensile strength (TS) of 780 MPa or more and has excellent characteristics in ductility, ductility, tensile properties. Specific characteristics of the surface And the ability to pass Sheet of material which can be obtained by providing a defined chemical composition. Advance and microstructure of steel which consists of the following components in the unit The percentage by area is 20-50% ferrite, 5-25% benitic ferrite, 1-10% martensite, and 5-% temp martensite. 15 and which contains the following components in the unit. Percent by volume is a fixed austenite of 10 percent or more. Where austenite The average grain size of this fixed austenite is 2 m3 or less, the mean Mn load in the austenitic austenite in percent, with the mass at least 1.2 times the Mn load in Such steel plates are in percentage by mass. Such a fixed austenide has an average free path of 1.2 m3 or less. And that martensite has an average free trajectory of 1.2 mx or less.

Claims (1)

: This invention discloses a high strength steel plate with a tensile strength (TS) of 780 MPa or more and has excellent characteristics in ductility, ductility, tensile properties. Specific characteristics of the surface And the ability to pass Sheet of material which can be obtained by providing a defined chemical composition. Advance and microstructure of steel which consists of the following components in the unit The percentage by area is 20-50% ferrite, 5-25% benitic ferrite, 1-10% martensite, and 5-% temp martensite. 15 and which contains the following components in the unit. Percent by volume is a fixed austenite of 10 percent or more. Where austenite The average grain size of this fixed austenite is 2 m3 or less, the mean Mn load in the austenitic austenite in percent, with the mass at least 1.2 times the Mn load in Such steel plates are in percentage by mass. Such a fixed austenide has an average free path of 1.2 m3 or less. And that martensite has an average free trajectory of 1.2 m3 or less. (Item one) which will appear on the advertisement page: 1. High strength steel plate which is assembled with The chemical composition which consists of the following components in percent by mass: C: 0.08% or more and 0.35% or less, Si: 0.50% or more and 2.50% or less. , Mn: 1.50 percent or more and 3.00 percent or less, P: 0 percent.