The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 15, 2005
Filed:
Sep. 15, 1998
Eizo Yoshitake, Middletown, OH (US);
Alan R. Mckague, Monroe, OH (US);
Eizo Yoshitake, Middletown, OH (US);
Alan R. McKague, Monroe, OH (US);
Armco Inc., Middletown, OH (US);
Abstract
A ferritic non-ridging stainless steel and process therefor. A chromium alloyed steel melt containing sufficient titanium and nitrogen but a controlled amount of aluminum is cast into an ingot or continuously cast into a strip or a slab having an as-cast fine equiaxed grain structure substantially free of columnar grains. The as-cast steel contains 0.08% C, at least about 8% Cr, up to 1.50% Mn, <0.020% Al, ≦0.05% N, ≦1.5% Si, <2.0% Ni, Ti≧0.10%, the ratio of (Ti×N)/Al≧0.14, all percentages by weight, the balance Fe and residual elements. Preferably, the titanium is controlled so that (Ti/48)/[(C/12)+(N/14)]>1.5. A hot processed sheet may be formed from a continuously cast slab without grinding the surfaces of the slab. The hot processed sheet may be descaled, cold reduced to a final thickness and recrystallization annealed. Annealing the hot processed sheet prior to cold reduction is not required to obtain an annealed sheet essentially free of ridging and having high formability.