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. 12, 2013
Filed:
Dec. 22, 2009
Katsumi Kojima, Hiroshima, JP;
Takumi Tanaka, Hiroshima, JP;
Masaki Tada, Hiroshima, JP;
Makoto Aratani, Chiba, JP;
Hiroki Iwasa, Kanagawa, JP;
Katsumi Kojima, Hiroshima, JP;
Takumi Tanaka, Hiroshima, JP;
Masaki Tada, Hiroshima, JP;
Makoto Aratani, Chiba, JP;
Hiroki Iwasa, Kanagawa, JP;
JFE Steel Corporation, , JP;
Abstract
A method provides a slab by continuous casting of a steel having a component composition of, in mass %, C: 0.005% or less, Mn: 0.05 to 0.5%, Al: 0.01 to 0.10%, N: 0.0010 to 0.0070%, B: 0.15×N to 0.75×N (0.15 to 0.75 in terms of B/N), and one or both of Nb: 4×C to 20×C (4 to 20 in terms of Nb/C) and Ti: 2×C to l0×C (2 to 10 in terms of Ti/C), and the balance of Fe and inevitable impurity elements; rough rolling the slab; finish rolling the rough-rolled slab wherein 5% or more and less than 50% of the total amount of rolling reduction in the finish rolling is hot-rolled at a temperature lower than the Artransformation point; winding the hot-rolled steel sheet at a winding temperature of 640 to 750 ° C.; pickling the coiled steel sheet; cold rolling the pickled steel sheet at a rolling reduction rate of 88 to 96%; and annealing the cold-rolled steel sheet in a temperature range of higher than 400 ° C. to a temperature that is 20 ° C. lower than the recrystallization temperature.