ArcelorMittal S.A.
HOT ROLLED STEEL AND A METHOD OF MANUFACTURING THEREOF

Abstract:

A hot rolled steel having a composition including comprising of the following elements 0.01%.ltoreq.Carbon.ltoreq.0.1%, 0.2%.ltoreq.Manganese.ltoreq.2%, 0.2%.ltoreq.Silicon.ltoreq.1.5%, 0.01%.ltoreq.Aluminum.ltoreq.2%, 0.1%.ltoreq.Tin.ltoreq.1%, 0.1%.ltoreq.Copper.ltoreq.0.5%, 0.001%.ltoreq.Niobium.ltoreq.0.1%, 0.002%.ltoreq.Phosphorus.ltoreq.0.02%, 0%.ltoreq.Sulfur.ltoreq.0.005%, 0%.ltoreq.Nitrogen.ltoreq.0.01%, with 0.3%.ltoreq.Sn+Cu.ltoreq.1.2% and can contain one or more of the following optional elements 0%.ltoreq.Titanium.ltoreq.0.1%, 0%.ltoreq.Vanadium.ltoreq.0.1%, 0%.ltoreq.Chromium.ltoreq.1%, 0%.ltoreq.Molybdenum.ltoreq.0.5%, 0%.ltoreq.Calcium.ltoreq.0.01%, 0%.ltoreq.Boron.ltoreq.0.01%, 0%.ltoreq.Magnesium.ltoreq.0.05%, 0%.ltoreq.Calcium.ltoreq.0.01%, 0%.ltoreq.Cerium.ltoreq.0.1%, 0%.ltoreq.Boron.ltoreq.0.05%, 0%.ltoreq. Nickel.ltoreq.0.01%, the remainder composition being composed of iron and unavoidable impurities caused by processing, the microstructure of said steel sheet including in area fraction, 75% to 95% Ferrite, 1% to 15% Pearlite and optionally Bainite is between 0% and 25% wherein the average grain size of all the microstructural constituent is less than 15 microns.