Alternating Layer Thermal Barrier Coatings for Sand Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Turbine engine components in desert environments suffer from sand-related distress due to fluid sand deposits penetrating thermal barrier coatings, leading to spallation and accelerated oxidation of exposed metal, necessitating frequent repairs.
Innovation Solution
A thermal barrier coating system with alternating layers of oxyapatite and/or garnet combined with stabilized zirconia, hafnia, or titania materials, stabilized by rare earth oxides such as lanthanum, cerium, and praseodymium, which forms a barrier against molten sand infiltration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional thermal barrier coatings are used in desert environments, then the coating provides thermal insulation, but fluid sand deposits penetrate the coating causing spallation and accelerated oxidation
Solution Approach 1:
The coating is divided into multiple alternating layers of different materials (e.g., yttria-stabilized zirconia and garnet or oxyapatite) to create a composite structure. Each layer provides different functional properties, with the alternating arrangement creating a stepped morphology that mechanically interlocks and resists sand penetration while maintaining thermal insulation performance.
Solution Approach 2:
The invention uses composite material systems combining ceramic materials with different properties. The alternating layers of zirconia-based and garnet or oxyapatite-based materials create a composite coating that leverages the thermal insulation properties of zirconia while the garnet/oxyapatite layers provide enhanced resistance to sand penetration and chemical stability.
2Device complexity
If single-layer thermal barrier coatings are used, then the coating structure is simple, but the coating is more susceptible to sand-related distress and spallation
Solution Approach 1:
The coating is divided into multiple alternating layers of different materials (e.g., yttria-stabilized zirconia and garnet or oxyapatite) to create a composite structure. Each layer provides different functional properties, with the alternating arrangement creating a stepped morphology that mechanically interlocks and resists sand penetration while maintaining thermal insulation performance.
Solution Approach 2:
Different regions of the coating have different material compositions and properties optimized for specific functions. The zirconia-based layers provide thermal insulation, while the garnet or oxyapatite layers provide enhanced mechanical interlocking and sand resistance. This local differentiation of material properties maximizes overall coating performance.
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 coating system effectively prevents molten silicate material penetration and enhances durability by forming a robust barrier against sand-induced distress, reducing maintenance and operational downtime.
Implementation Method 1
The coating system effectively prevents molten silicate material penetration and enhances durability by forming a robust barrier against sand-induced distress
Implementation Method 2
a stabilized material selected from the group consisting of zirconia, hafnia and titania, the stabilized material being stabilized by a rare earth material
Implementation Method 3
Sand related distress is caused by the penetration of fluid sand deposits into the thermal barrier coatings which leads to spallation and accelerated oxidation of any exposed metal
Data Source
AI summary
A thermal barrier coating system for use on a turbine engine component which reduces sand related distress is provided. The coating system comprises at least one first layer of a stabilized material selected from the group consisting of zirconia, hafnia, and titania and at least one second layer containing at least one of oxyapatite and garnet. Where the coating system comprises multiple first layers and multiple second layers, the layers are formed or deposited in an alternating manner.