PtAl2 Layer Thermal Barrier Coating Adhesion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current thermal barrier coating systems for gas turbine components face challenges in achieving optimal adhesion and spall resistance due to surface roughness and the formation of thermally grown oxides, which affect the performance and longevity of the coatings at elevated temperatures.

Innovation Solution

A method involving the formation of a coated article with a substrate, an aluminide layer, a PtAl2 layer, and a YSZ thermal barrier layer, where the aluminide layer is formed through gas phase deposition of aluminum-containing materials and platinum is applied via electroplating, followed by diffusion to create a continuous PtAl2 phase, enhancing surface smoothness and adhesion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a thermal barrier coating is applied to a superalloy substrate, then the component can operate at elevated temperatures, but the coating may form thermally grown oxides and surface roughness that reduce adhesion and spall resistance

Engineering Contradiction:
Improveoperating temperatureVSAvoidcoating adhesion and spall resistance
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

A platinum layer is applied to the substrate before the aluminum-containing coating, and diffusion is performed to create a continuous PtAl2 layer. This preliminary action prepares a smooth, adhesive surface that prevents thermally grown oxide formation during subsequent high-temperature operation, thereby maintaining coating reliability at elevated temperatures

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The diffusion process changes the chemical composition and microstructure of the bond coat by creating a continuous PtAl2 phase. This parameter change transforms the surface properties to achieve smoothness and enhanced adhesion, directly addressing the reliability issue while enabling high-temperature operation

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If diffusion is performed to create a continuous PtAl2 layer, then surface smoothness and adhesion are enhanced, but the process complexity increases

Engineering Contradiction:
Improvesurface smoothnessVSAvoidcoating process complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The platinum layer and aluminum-containing coating are combined through diffusion to form a continuous PtAl2 layer. This merging of two separate coating steps into a single integrated process achieves surface smoothness and enhanced adhesion while managing process complexity through consolidation

Inventive Principle:
Principle #5Merging (Combining)

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 method improves the adhesion and spall resistance of the thermal barrier coatings by creating a smooth surface and a stable PtAl2 layer, thereby enhancing the thermal insulation and durability of the coatings at elevated temperatures.

Implementation Method 1

an aluminide layer is formed through gas phase deposition of aluminum-containing materials

Methodology Applied
Scientific EffectGas phase deposition: Chemical Vapour Deposition

Implementation Method 2

platinum is applied via electroplating

Methodology Applied
Scientific EffectElectroplating: Electroplating

Implementation Method 3

followed by diffusion to create a continuous PtAl2 phase

Methodology Applied
Scientific EffectDiffusion: Diffusion

Data Source

PatentEP1726685B1Manufacturing method of a thermal barrier coating
Publication Date: 2012.07.11 TURBINE OVERHAUL SERVICES PTE
  • EP1726685B1 patent drawingFigure 1~2
  • EP1726685B1 patent drawingFigure 3

AI summary

A coated article includes a substrate (20) and a thermal barrier layer (22). An aluminide layer (26) is between the substrate (20) and the thermal barrier layer (22). A PtAl2 layer (24) is between the aluminide layer (26) and the thermal barrier layer (22).