MUMBAI, India, June 13 -- Intellectual Property India has published a patent application (202517050960 A) filed by Arcelormittal, Luxembourg, on May 27, for 'cold rolled and heat-treated steel sheet and a method of manufacturing thereof.'
Inventor(s) include Musik, Celine; and Hebert, Veronique.
The application for the patent was published on June 13, under issue no. 24/2025.
According to the abstract released by the Intellectual Property India: "A cold rolled and heat-treated steel sheet, the steel comprising, 0.15% = carbon = 0.25%, 2.2% = manganese = 3%, 1.1% = silicon = 2%, 0% = aluminum =0.09%, 0.05%= molybdenum = 0.5%, 0.001%= titanium = 0.06%, 0.001%= boron = 0.010%, 0%= phosphorus = 0.02%, 0%= sulfur = 0.03%, 0% = nitrogen = 0.09%, 0%= chromium = 1%, 0%= copper = 2%, 0%= niobium = 0.06%, 0%= vanadium =0.1%, 0%= calcium = 0.005%, 0%= Magnesium = 0.05%, 0%= Zirconium = 0.05%, 0%= Cerium = 0.1%, and the balance including iron and unavoidable impurities, the steel sheet having a core microstructure comprising 15% to 70% of Bainite, 15% to 70% of Partitioned martensite, 10% to 30% of ferrite, 9% to 22% of residual austenite in Bainite and Partitioned Martensite and 0% to 5% fresh martensite in area fractions, and a ferrite-enriched layer extending up to 90 microns from both surfaces of said steel sheet, such ferrite-enriched layer having two sub layers wherein a first sub-layer which is adjacent to the surface of the steel sheet has an average ferrite percentage from 40% to 80% in area fraction with a gradient of ferrite (?F) that is from 20% to 70%, ?F being the difference between the ferrite content of the top of first sub-layer and the ferrite content of the bottom of said second sub-layer and a second sub-layer which is topmost layer of the ferrite enriched layer, said second sub-layer having a ferrite percentage from 70% to 98% in area fraction and including internal oxides of manganese and silicon."
The patent application was internationally filed on Dec. 14, 2022, under International application No.PCT/IB2022/062197.
Disclaimer: Curated by HT Syndication.
