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:
Jun. 14, 2005
Filed:
Nov. 06, 2002
Shigenori Tanaka, Kimitsu, JP;
Toyoichiro Higashi, Kimitsu, JP;
Masahiro Doki, Kimitsu, JP;
Jun Fukuda, Kimitsu, JP;
Hiroshi Ohba, Kimitsu, JP;
Mitsuo Uchimura, Kimitsu, JP;
Shigenori Tanaka, Kimitsu, JP;
Toyoichiro Higashi, Kimitsu, JP;
Masahiro Doki, Kimitsu, JP;
Jun Fukuda, Kimitsu, JP;
Hiroshi Ohba, Kimitsu, JP;
Mitsuo Uchimura, Kimitsu, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
A billet produced by continuous casting having little central segregation, in particular a billet of high carbon steel produced by continuous casting, and a manufacturing method therefor are provided. In the continuous casting billet, the size of the dendritic equiaxed crystal in a billet central portion is reduced to be not more than 6 mm. For this purpose, electromagnetic stirring is performed so that the inclining angle of the primary dendrite within 10 mm of a billet surface layer is increased to be not less than 10°. Furthermore, the mechanical soft reduction is performed during continuous casting so that the diameter of the center porosity in the billet central portion is reduced to be not more than 4 mm. Thereby, in particular in the manufacturing of the continuous casting billet having a carbon content of not less than 0.6% by mass and a billet size of not more than 160 mm can be provided a billet in which breaking troubles in wire drawing after rolling to a rod are reduced by reducing the central segregation in the billet.