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. 23, 1992
Filed:
Oct. 30, 1989
Applicant:
Inventors:
Masanori Kato, Tokyo, JP;
Toshio Kamatani, Tokyo, JP;
Keiichi Nakagawa, Tokyo, JP;
Kiyoshi Kawasaki, Tokyo, JP;
Yutaka Yano, Tokyo, JP;
Assignee:
NKK Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D / ;
U.S. Cl.
CPC ...
75416 ; 148208 ; 148513 ; 148668 ; 420 71 ; 420104 ; 75623 ;
Abstract
A method for manufacturing a low carbon ferrochrome with a high chromium content of at least 70 weight % Cr comprising the steps of at least once nitriding and crushing a low carbon ferrochrome to form a crushed ferrochrome nitride and subjecting the crushed ferrochrome nitride to an acid treatment comprising introducing the crushed ferrochrome nitride into an acid solution and stirring the resultant mixture of the ferrochrome nitride and the acid solution, to remove iron. The acid treated ferrochrome nitride is denitrided by heating in a vacuum.