Process for manufacturing thin strip of ferritic stainless steel, and thin strip thus obtained

US6106638A · kind A · utility

Assignee

• USINOR · FR

Inventors

• Philippe Paradis · Lillers, FR
• Philippe Martin · Herstal, BE

Key dates

• Filing date: May 11, 1998
• Grant date: Aug 22, 2000
• Expiry date: May 11, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C21D1/19
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The subject of the invention is a process for manufacturing ferritic stainless steel strip, in which a strip of a ferritic stainless steel, of the type containing at most 0.12% of carbon, at most 1% of manganese, at most 1% of silicon, at most 0.040% of phosphorus, at most 0.030% of sulfur and between 16 and 18% of chromium, is solidified, directly from liquid metal, between two close-together, internally-cooled, counterrotating rolls with horizontal axes, wherein said strip is then cooled or left to cool so as to avoid making it remain within the austenite to ferrite and carbides transformation range, wherein said strip is coiled at a temperature of between 600.degree. C. and the martensitic transformation temperature Ms, wherein the coiled strip is left to cool at a maximum rate of 300.degree. C./h down to a temperature of between 200.degree. C. and ambient temperature and wherein said strip then undergoes box annealing. The subject of the invention is also a ferritic stainless steel strip of the type containing at most 0.12% of carbon, at most 1% of manganese, at most 1% of silicon, at most 0.040% of phosphorus, at most 0.030% of sulfur and between 16 and 18% of chromium, wherei…