초록 ▼

A blade for a fluid flow engine, especially a gas turbine, has a protective coating against injurious attack by the propellant or working medium. A metal blade having a diffusion layer or a sprayed coating for inhibiting corrosion is known. Such coating renders the blade highly resistant against hea

A blade for a fluid flow engine, especially a gas turbine, has a protective coating against injurious attack by the propellant or working medium. A metal blade having a diffusion layer or a sprayed coating for inhibiting corrosion is known. Such coating renders the blade highly resistant against heavily erosive and corrosive attack, especially by pulverized coal combustion gas or similar agents. The present blade is made of ceramic material, especially a dense ceramic material with a surface layer of at least one of the following materials: TiN, TiC, B4C, BN and titanium carbon nitride. These materials are easy to apply and provide a good bond with the ceramic material. If the ceramic materials are silicon carbide (SiC) or silicon nitride (Si3N4) an especially good bond is achieved. This coating strongly resists removal, as it does oxidation and heat. Local removal down to the ceramic material, as it may result from rather long service, is recognizable immediately. These coating materials can be applied to give adequate quality and satisfactory repeatability by using the known CVD (chemically vapor deposited) or the PVD (physical vapor deposited) process.

대표청구항 ▼

A blade for a turbomachine, comprising a blade body of a dense ceramic material and a protective coating on at least certain surface portions of said blade body, said protective coating being selected from the group consisting of titanium nitride, titanium carbide and titanium carbon nitride, said p

A blade for a turbomachine, comprising a blade body of a dense ceramic material and a protective coating on at least certain surface portions of said blade body, said protective coating being selected from the group consisting of titanium nitride, titanium carbide and titanium carbon nitride, said protective coating having been applied by chemical vapor deposition (CVD) or physical vapor deposition (PVD), whereby said blade has an improved resistance to both corrosion and erosion as compared to said blade without said protective coating.