A process for producing a weather-resistant continuous thin strip casting - steel, in which a high strength with a quality of 700 mpa.

摘要

A manufacturing method for a weather-resistant continuous strip casting plant - steel, which a high strength with a quality of 700 mpa, comprising the following steps:1) Casting a said cast strip with a thickness of 1 – 5 mm, using a continuous twin - rollers - the casting unit, wherein the casting tape of a chemical composition in percent by weight, such as in the following: c 0,03 – 0,1%, si ≤ 0,4%, mn 0,75 – 2,0%, p 0,07 – 0,22%, s ≤ 0,01%, n ≦ 0,012% and cu 0,25 – 0,8% and at least one micro alloy - element selected from nb, v, ti and mo, with a content of nb 0,01 – 0,1%, v 0,01 – 0,1%, ti 0,01 – 0,1% and mo 0,1 – 0,5% and wherein the balance fe and unavoidable impurities are;2) Cooling of said cast strip, wherein the cooling rate is greater than 20°C. / s is;3) Of said cast strip online - hot rolling under a hot-rolling temperature of 1050 – 1250°C, a reduction ratio of 20 – 50% and a forming velocity of 20 s^–1, wherein the thickness of the steel strip according to the hot rolling of 0,5 – 3,0 mm, and online - austenite - recrystallization after the hot-rolling takes place of said cast strip;4) Cooling of the hot rolled strip, wherein the cooling rate of 10 – 80°C. / s is;5) coiling of the hot rolled strip, wherein the coilingtemperatur of the hot rolled strip is controlled such that it 500 – 650°C; andthe finally resulting steel strip has a microstructure, which essentially consists of a homogeneous acicular of ferrite and bainite.