Coated silicon comprising material for protection against environmental corrosion
a technology of environmental corrosion and coating silicon, which is applied in the direction of superimposed coating process, chemical vapor deposition coating, coating, etc., can solve the problems of high temperature durability of the components within the engine, and reducing the number of layers of silicon. , to achieve the effect of reducing the formation of silicon glass and reducing the formation of silicate glass
Inactive Publication Date: 2009-07-02
GENERAL ELECTRIC CO
View PDF3 Cites 2 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
The coating system significantly reduces silicate glass formation on silicon materials, enhancing their durability and protective performance against corrosion in high-temperature environments, thereby improving the longevity and efficiency of gas turbine engine components.
Problems solved by technology
However, as operating temperatures increase, the high temperature durability of the components within the engine must correspondingly increase.
However, some silicon substrates may recede and lose mass as a result of formation of volatile Si species, particularly Si(OH)x and SiO when exposed to high temperature, aqueous environments, thus necessitating the use of a protective coating thereon.
While the current state of the art EBCs, which are typically multi-layer EBCs, may be effective in preventing water vapor recession of the ceramic matrix composite (CMC) substrate, both BSAS, SiC and some rare earth silicates such as some silicates disclosed in U.S. Pat. No. 6,759,151 may be susceptible to silicate glass formation when in contact with sulfate salt deposits as operating conditions continue to increase.
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0015]Applicant has determined through testing that silicon comprising materials may adversely react with deposited sulfates. For example, this material may react with Na2SO4 at temperatures such as about 1700° F. (927° C.) and higher, and MgSO4 / CaSO4 may react at temperatures such as about 2200° F. (1204° C.) and higher. This reaction causes corrosion and forms a silicate glass from the silicon comprising material. Deep pitting and CO evolution can degrade the performance of the silicon comprising material. Additionally, this may prevent EBCs from acting as optimal water recession barriers for silicon comprising substrates as silicate glass has a high recession rate.
[0016]Embodiments of the present invention improve upon prior coated silicon comprising materials, particularly EBC systems used upon silicon comprising material substrates. These embodiments are generally applicable to components that operate within environments of relatively high temperatures, and are thus subjected t...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| temperatures | aaaaa | aaaaa |
| temperatures | aaaaa | aaaaa |
| thickness | aaaaa | aaaaa |
Login to View More
Abstract
In accordance with an embodiment of the invention, an article is disclosed. The article comprises a gas turbine engine component substrate comprising a silicon material; and an environmental barrier coating overlying the substrate, wherein the environmental barrier coating comprises cerium oxide, and the cerium oxide reduces formation of silicate glass on the substrate upon exposure to corrodant sulfates.
Description
GOVERNMENT RIGHTS[0001]The invention was made in part under contract number NAS3-01135 awarded by the Government (NASA). Accordingly, the Government has certain rights in this invention.FIELD OF THE INVENTION[0002]This invention relates to protecting materials comprising silicon from environmental corrosion, such as that experienced in the hostile thermal environment of a gas turbine engine. More particularly, the invention relates to an environmental barrier coating (EBC) system for use on silicon comprising substrates for providing protection against environmental corrosion.BACKGROUND OF THE INVENTION[0003]Higher operating temperatures for gas turbine engines are continuously sought in order to increase efficiency. However, as operating temperatures increase, the high temperature durability of the components within the engine must correspondingly increase. In this regard, materials comprising silicon, particularly those with silicon carbide (SiC) as a matrix material or a reinforc...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Applications(United States)
IPC IPC(8): C23C16/40C23C16/42
CPCC04B41/009C23C28/3455C04B41/52C04B41/87C04B41/89C23C28/042C04B41/5045C23C28/345C23C28/322C04B41/4527C04B41/5096C04B41/5037C04B41/5024C04B35/565C04B35/584C04B35/806
Inventor HAZEL, BRIAN THOMAS
Owner GENERAL ELECTRIC CO