ArcelorMittal S.A.
Manufacturing Method for Hot Rolled Steel Sheet

Abstract:

A method for the fabrication of a hot rolled steel includes providing a liquid metal comprising a certain chemical composition; carrying out a vacuum or SiCa treatment, the chemical composition including, expressed by weight 0.0005%.ltoreq.Ca.ltoreq.0.005%, if a SiCA treatment is carried out; dissolving quantities of Ti and N in the liquid metal so as to satisfy (% [Ti]).times.(% [N])<6.10.sup.-4%.sup.2; casting the steel to obtain a cast semi-finished product; rolling the cast semi-finished product with an end-of-rolling temperature between 880.degree. C. and 930.degree. C., a reduction rate of the penultimate pass being less than 0.25, and a start-of-rolling temperature of the penultimate pass being less than 960.degree. C. to obtain a hot-rolled product, then cooling the hot rolled product at a rate between 20 and 150.degree. C./s to obtain a hot rolled steel sheet; and coiling the hot rolled product to obtain a hot rolled steel sheet.