Arcelormittal

Pascal Lorenzini

A heat treated cold rolled steel sheet having a composition comprising of the following elements, 0.1%≤Carbon≤0.25%, 2.15%≤Manganese≤3.0%, 1%≤Silicon≤0.8%, 0.1%≤Aluminum≤0.9%, 0.05%≤Chromium≤0.5%, 0%≤Phosphorus≤0.09%, 0%≤Sulfur≤0.09%, 0%≤Nitrogen≤0.09%, 2.4%≤C+Mn≤3%, 0%≤Niobium≤0.1%, 0%≤Titanium≤0.1%, 0%≤Vanadium≤0.1%, 0%≤Molybdenum≤1%, 0%≤Nickel≤1%, 0%≤Calcium≤0.005%, 0%≤Boron≤0.01%, 0%≤Cerium≤0.1%, 0%≤Magnesium≤0.05%, 0%≤ Zirconium≤0.05% the remainder being composed of iron and unavoidable impurities, the microstructure of said steel sheet including, 20% to 70% Martensite, 5 to 60% of Inter-critical Ferrite, 5 to 30% of Transformed Ferrite, 8% to 20% of Residual Austenite and 1 to 20% Bainite, wherein the cumulated amount of Inter-critical and Transformed Ferrite is between 15% and 65%.

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Woippy, France

Pascal Lorenzini