Dual-Layer Barrier Coating for Gas Turbine Metallic Isolation
Solution Overview
Problem
The interaction between metallic structures and ceramic matrix composite components in gas turbine engines leads to degradation due to chemical diffusion at high temperatures, limiting the operating temperature of the engines.
Innovation Solution
A dual-layer barrier coating is applied to the metallic support components, comprising a refractory metal precursor coating that forms an oxide layer when heated, preventing silicon ingress from the ceramic matrix composite and reducing chemical interaction with the metallic structures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If ceramic matrix composite components are used to enable higher operating temperatures, then the temperature capability of the engine is improved, but chemical interaction between the ceramic composite and metallic support structures causes degradation of the metallic structures
Solution Approach 1:
A barrier coating is introduced as an intermediary layer between the ceramic matrix composite component and the metallic support structure. This coating prevents direct chemical interaction while allowing the system to operate at high temperatures. The barrier coating acts as a mediator that isolates the two materials, enabling the ceramic composite to withstand high temperatures without causing degradation to the metallic support structures through chemical diffusion or reaction.
2Reliability
If a barrier coating is applied to prevent chemical interaction, then the reliability of metallic structures is improved, but the complexity of the engine assembly increases
Solution Approach 1:
The barrier coating is applied in advance to the metallic support structures before final assembly of the engine components. This preliminary action ensures that the protective layer is already in place before the ceramic matrix composite components are installed, preventing chemical interaction from the outset. By performing the coating operation beforehand, the complexity of the assembly process is reduced, as the coating application is separated from the final assembly operations.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The barrier coating effectively isolates the metallic components from the ceramic matrix composite, preventing degradation and allowing the gas turbine engines to operate at higher temperatures without compromising the metallic structures.
Implementation Method 1
the precursor coating is heated to a predetermined temperature to form a dual layer barrier coating comprising an oxide layer along an exterior edge of a base layer from the precursor coating
Implementation Method 2
the silicon in the silicon-comprising composite component is restricted from ingress into the metallic support component by the oxide-comprising layer
Data Source
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AI summary
A barrier coating for isolating a metallic support component from a composite component in a gas turbine engine is provided. The barrier coating may be applied to the metallic support component so that when the ceramic component is mounted on the metallic support component the barrier coating is engaged.