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:
Nov. 06, 2007
Filed:
Sep. 11, 2003
Eiichi Ishii, Hyogo, JP;
Takumi Sone, Osaka, JP;
Yukihiro Sato, Hyogo, JP;
Kei Demizu, Osaka, JP;
Hideo Kakutani, Osaka, JP;
Koichi Tanaka, Osaka, JP;
Shinichi Tanaka, Osaka, JP;
Noriyoshi Tsuji, Osaka, JP;
Eiichi Ishii, Hyogo, JP;
Takumi Sone, Osaka, JP;
Yukihiro Sato, Hyogo, JP;
Kei Demizu, Osaka, JP;
Hideo Kakutani, Osaka, JP;
Koichi Tanaka, Osaka, JP;
Shinichi Tanaka, Osaka, JP;
Noriyoshi Tsuji, Osaka, JP;
Abstract
A method of carburizing treatment is proposed in which if carburizing is carried out at a low temperature, carbon will not turn amorphose and deposit on the surface of a titanium metal but reliably penetrate into between metallic atoms. It is a method of surface treatment of a titanium metal comprising the steps of heating the titanium metal to a temperature of 400-690° C. in a cleaning gas atmosphere containing hydrogen gas, subjecting the surface of the titanium metal to cleaning by applying a DC voltage of 200-1500 V, and plasma carburizing in an atmosphere comprising a carburizing gas having an atomic weight ratio of hydrogen atoms (H) to carbon atoms (C) adjusted to 1≦H/C≦9 at a pressure of 13-400 Pa and a temperature of 400-690° C. Ionization reaction in the gas is suppressed suitably. Because there exists no excessive carbon which is not used for carburization but turns soot or glass-like carbon, in the atmosphere during carburization, carburizing reaction progresses smoothly.