PROCESS FOR THE PRODUCTION OF THIN TRIP-STEEL STRIPS AND THIN STRIPS OBTAINED USING SUCH A PROCESS

摘要

the invention is directed to a process for the manufacture of foil type trip steel, according to which, it runs directly from liquid steel strip thickness between 1.5 and 10 mm, preferably 1 to 5 mm, the steel with the composition (% by weight) between 0.05 and 0.25% c, (mn + cu + ni) per cent between 0.5 and 3 (si + al) between 0.1 and 4 (p + sn + have + sb) less than or equal to 0.1% (ti + nb + v + zr + rare earths)% less than 0.3, cr% less than 1 mb per cent lower than 1 v per cent lower than 1.the remainder of iron and impurities arising from the development, there is a line of the hot rolling strip at a temperature higher than the temperature of the steel with a ar3rate of reduction between 25% and 70%.in one or more passes, a forced cooling is carried out by the band at a rate of between 5 and 100 c / s, and let be the band at a temperature in the range.a 550 and setting during the time required for processing is to produce a residual austenite bainite with a share of more than 5 per cent, while avoiding the formation of pearlite.we interrupt this transformation by a second forced cooling of the band, which leads to a temperature below setting, there is a winding of the strip to a tempu00e9rata less than 350 c. the invention also relates to a thin strip of steel type trip which can be obtained by the previous process.