Lattice Structure Thermal Barrier Coating Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ceramic thermal barrier coatings in gas turbine engines face adherence issues due to extreme heat and mechanical spallation, particularly in regions with high surface curvature, leading to reduced effectiveness and potential breakage.
Innovation Solution
A lattice structure is integrated into the exterior surface of gas turbine engine components, which is manufactured using additive metal processes and covered by a thermal barrier coating, enhancing adhesion and reducing spallation by increasing the surface area for coating adherence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a ceramic thermal barrier coating is applied to the exterior surface of gas turbine components, then the operating temperature of the component is reduced, but the coating suffers from adhesion failure and mechanical spallation under extreme heat and stress
Solution Approach 1:
The coating system is segmented into multiple functional layers: a metallic bondcoat layer applied directly to the substrate, and a ceramic topcoat layer applied over the bondcoat. This segmentation allows each layer to perform its specialized function - the bondcoat provides adhesion and oxidation resistance, while the topcoat provides thermal barrier protection, thereby improving overall coating reliability under extreme conditions
Solution Approach 2:
The invention uses a composite coating structure combining dissimilar materials - a metallic alloy bondcoat (typically nickel-based) and a ceramic topcoat (typically yttria-stabilized zirconia). This composite structure leverages the complementary properties of both materials: the metal provides ductility and adhesion, while the ceramic provides high-temperature resistance, resolving the adhesion failure problem
2Ease of manufacture
If the lattice structure is fully removed via finishing process, then the surface is smooth, but the thermal barrier coating adhesion is reduced
Solution Approach 1:
The lattice structure retention applies local quality modification - instead of uniformly removing all support artifacts, the invention selectively retains lattice structures in specific regions where coating adhesion is critical, while removing them in regions where they would cause operational problems. This localized approach optimizes both adhesion and manufacturability
3Adaptability or versatility
If additive metal manufacturing is used to create the lattice structure, then complex geometries are achieved, but surface roughness and artifact removal complexity increase
Solution Approach 1:
The additive manufacturing process serves multiple functions: it creates the complex component geometry, generates the lattice structure for adhesion enhancement, and produces the substrate for coating application. By making the manufacturing process multi-functional, the invention reduces overall device complexity despite the inherent complexity of additive manufacturing
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 lattice structure improves the adherence of the thermal barrier coating, reducing mechanical spallation and maintaining coating integrity under extreme heat loads, thereby enhancing the performance and durability of gas turbine components.
Implementation Method 1
enhancing adhesion and reducing spallation by increasing the surface area for coating adherence
Implementation Method 2
The presence of the thermal barrier coating significantly reduces the operating temperature of the component
Data Source
AI summary
A gas turbine engine including a compressor section, a combustor section fluidly connected to the compressor section, a turbine section fluidly connected to the combustor section, and a plurality of gas path components exposed to a primary fluid flowpath through the compressor section, the combustor section and the turbine section. At least one of the gas path components includes an exterior facing surface, a lattice structure extending outward from the exterior facing surface, the lattice structure being integral to the exterior facing surface, and a thermal barrier coating adhered to at least a portion of the exterior facing surface and the lattice structure.