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:
Sep. 02, 2003
Filed:
May. 14, 1999
Tadahiro Ohmi, Miyagi-ken, JP;
Takahisa Nitta, Tokyo, JP;
Other;
Abstract
A method for forming an oxidation-passive layer having high corrosion resistance to highly oxidizing materials such as ozone; a stainless steel and a titanium base alloy having corrosion resistance to an ozone containing fluid; and a fluid containing part, a process apparatus, and a fluid feed/discharge system made by using the same. The method comprises the steps of heat-treating the surface of a stainless steel or titanium-base alloy having an Al content of 0.5 percent by weight to 7 percent by weight either at 300° C. to 700° C. in a mixed gas atmosphere composed of an inert gas and 500 ppb to 1 percent H O gas or 1 ppm to 500 ppm oxygen gas, or alternatively at 20° C. to 300° C. in a mixed gas atmosphere composed of an oxygen gas and at least 100 ppm ozone gas to form an oxidation-passive layer containing an aluminum oxide or a titanium oxide.