Patent ID: 6086689
Filing Date: 2000-07-11
Classification: C21D,C22C

Abstract:
A process for manufacturing a foil of ferritic stainless steel having an aluminum content, comprising hot rolling and cold rolling a ferritic stainless steel sheet having a composition comprising:iron0.005%<carbon<0.060%10%<chromium<23%0.1%<aluminum<3%0.003%<nitrogen<0.030%0.1%<manganese<2%0.1%<silicon<2%rare-earth elements in a proportion of between 0.03% and 0.15%, to a thickness of less than or equal to 1.5 mm, and then subjecting said steel sheet to the following treatments in the following order:a softening annealing treatment at a temperature of between 600.degree. C. and 1200.degree. C.,plating between two sheets of aluminum, the sum of the thicknesses of which is between 0.03 times and 0.32 times the thickness of the steel sheet, in order to obtain a three-layer laminate,rolling of the laminate to a thickness of between 0.05 mm and 0.25 mm, in order to form a foil,static diffusion annealing of the foil in a hydrogen atmosphere having a dew point below -30.degree. C., andfinish rolling the foil with a total degree of reduction of greater than 20%, such that the final roughness Ra of the foil is less than 0.25 .mu.m.