Filing Information

Inventor(s)	Tohru Arai · Hatsuhiko Oikawa ·
Assignee(s)	Kabushiki Kaisha Toyota Chuo Kenkyusho ·  View assignee updates
Attorney/Agent(s)	Berman, Aisenberg & Platt ·
Primary Examiner	Sam Silverberg ·
Application Number	US7130802
Filing date	12/08/1987
Issue date	12/27/1988
Predicted expiration date	12/08/2007
U.S. Classifications	427/431  · 427/399  ·
International Classifications	C04B 4181  ·
Kind Code	A
International Classifications	427399;431 ·
Foreign Priority	JP61294282 - 12/10/1986 ·

Patent Family

Abstract

A method for forming a layer of a carbide or nitride of a metallic element or boron nitride on the surface of a ceramics article. A molten salt bath is prepared by heating and melting a bath agent composed of boron oxide and/or borate, and at least one metallic element selected from Group IVa, Va, VIa elements, etc. An article to be treated which is made of silicon nitride, silicon carbide or sialon is immersed in the salt bath. This method provides a ceramics product with a uniform surface layer having superior frictional and electrical properties.

Independent Claims | See all claims (21)

1. 1. A method for surface treatment which comprises the steps of:preparing a molten salt bath by heating and melting a bath agent comprising boron oxide and/or borate and at least one member selected from the group consisting of a metallic element and a substance containing at least one metallic element, the metallic element being a Group IVa element, a Group Va element, a Group VIa element, calcium, manganese, boron, aluminum, silicon, magnesium, or a rare earth element, andimmersing an article made of silicon nitrite, silicon carbide or sialon in said molten salt bath,thereby forming a surface layer of a carbide or nitride of said metallic element or of boron nitride on the surface of said article.