Surface-treated titanium material excellent in oxidation resistance, production method thereof, and engine exhaust system

Abstract

Disclosed are a surface-treated titanium material that is excellent in oxidation resistance and allows the excellent oxidation resistance to last for a long period of time and the surface treatment itself to be applied safely at a low cost; the production method thereof; and an exhaust system thereof. A surface-treated titanium material produced by forming an oxidation-resistant baked film 5 μm or more in thickness on a substrate comprising commercially pure titanium or titanium-base alloy, and said baked film is formed by filling the gaps among particles comprising Al alloy containing Si by 10 at % or less or commercially pure aluminum with chemical compounds comprising a metallic element M (M represents one or more of Ti, Zr, Cr, Si and Al) and C and / or O.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to: a surface-treated titanium material that is excellent in oxidation resistance and thus used for a part such as an engine exhaust system requiring oxidation resistance; the production method thereof; and an exhaust system thereof.

[0003] 2. Description of the Prior Art

[0004] Titanium alloy has a higher specific strength in comparison with a generally used steel material and is increasingly applied to the field of transport vehicles, mostly automobiles, which are intensively directed to weight reduction. In the field, as a material for an exhaust pipe in an exhaust system around an engine, stainless steel is mainly used at present but the application of titanium to an exhaust system has been studied with the aim of weight reduction. The temperature of an exhaust system however rises up to 500° C. or higher at some sites. Hence, when a titanium alloy material which is not surface-trea...