Thermal Barrier Coating Temperature Control

Solution Overview

Problem

The high initial and running costs, as well as low speed of layer formation, associated with electron beam physical vapor deposition methods for applying thermal barrier coatings on heat-resistant members, necessitate a more cost-effective approach while maintaining thermal barrier properties and heat cycle durability.

Innovation Solution

A method involving the thermal-spraying of a suspension containing ceramic powder by high velocity flame spraying, maintaining the top coat layer temperature between 300° C and 450° C, to form a thermal barrier coating on a bond coat layer, which reduces costs and improves thermal barrier properties and durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If electron beam physical vapor deposition is used to form the top coat layer, then thermal barrier properties and heat cycle durability are ensured, but the initial cost and running cost become more than ten times higher than thermal spraying

Engineering Contradiction:

Improveheat cycle durabilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The invention changes the temperature parameter during thermal spraying to resolve the contradiction. By maintaining the top coat layer temperature at not lower than 300°C and not higher than 450°C during thermal spraying, the invention achieves both cost reduction (using thermal spraying instead of electron beam deposition) and maintains thermal barrier properties. This temperature control enables the formation of a dense top coat layer with equivalent performance to electron beam deposition while using the more cost-effective thermal spraying process.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If electron beam physical vapor deposition is used to form the top coat layer, then thermal barrier properties are ensured, but the layer formation speed becomes as low as a fraction of the speed by thermal spraying

Engineering Contradiction:

Improvethermal barrier propertiesVSAvoidlayer formation speed

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The invention changes the temperature parameter during thermal spraying to resolve the contradiction. By maintaining the top coat layer temperature at not lower than 300°C and not higher than 450°C during thermal spraying, the invention achieves both cost reduction (using thermal spraying instead of electron beam deposition) and maintains thermal barrier properties. This temperature control enables the formation of a dense top coat layer with equivalent performance to electron beam deposition while using the more cost-effective thermal spraying process.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If electron beam physical vapor deposition is used to form the top coat layer, then thermal barrier properties are ensured, but the running cost becomes about ten times higher than thermal spraying

Engineering Contradiction:

Improvethermal barrier propertiesVSAvoidrunning cost

Core Design Contradiction:

ReliabilityVSUse of energy by stationary object

Solution Approach 1:

The invention changes the temperature parameter during thermal spraying to resolve the contradiction. By maintaining the top coat layer temperature at not lower than 300°C and not higher than 450°C during thermal spraying, the invention achieves both cost reduction (using thermal spraying instead of electron beam deposition) and maintains thermal barrier properties. This temperature control enables the formation of a dense top coat layer with equivalent performance to electron beam deposition while using the more cost-effective thermal spraying process.

Inventive Principle:

Principle #35Parameter changes

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

This method allows for the formation of a thermal barrier coating at a lower cost and in shorter time than electron beam physical vapor deposition, while achieving equivalent thermal barrier properties and heat cycle durability, thereby reducing manufacturing costs and improving performance.

Implementation Method 1

forming the top coat layer by thermal-spraying a suspension containing ceramic powder by high velocity flame spraying

Methodology Applied

Scientific EffectThermal spraying:

Implementation Method 2

maintaining a temperature of the top coat layer at not lower than 300° C. and not higher than 450° C.

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS20230374643A1Method for applying thermal barrier coating and heat-resistant member

Publication Date: 2023.11.23 MITSUBICHI HEAVY IND AERO ENGINES LTD

AI summary

A method for applying a thermal barrier coating according to at least one embodiment of the present disclosure includes: a step of forming a top coat layer on a bond coat layer formed on a heat-resistant alloy base material of an object. The step of forming the top coat layer includes forming the top coat layer by thermal-spraying a suspension containing ceramic powder by high velocity flame spraying, while maintaining a temperature of the top coat layer at not lower than 300° C. and not higher than 450° C.