Compliant Attachment for Organic Matrix Composite Interfaces

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Organic matrix composite (OMC) components face delamination and structural wear due to thermal strain at interfaces with mating structures having different thermal expansion coefficients, leading to weak interfacial connections and structural integrity issues.

Innovation Solution

A compliant attachment with a thermal expansion coefficient intermediate between the OMC component and the mating component is bonded to the interfacing surface, using methods like transient liquid phase bonding, partial transient liquid phase bonding, or brazing, to mitigate thermal strain and enhance structural integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If OMC components are directly connected to mating structures with different thermal expansion coefficients, then the connection is simple and direct, but thermal strain causes delamination and structural wear at the interface

Engineering Contradiction:

Improvestructural integrityVSAvoidconnection structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

A compliant attachment is introduced as an intermediary component between the OMC body portion and the mating component. This compliant attachment has a coefficient of thermal expansion intermediate between the OMC and the mating component, serving as a thermal bridge that reduces thermal strain at the interface while maintaining structural integrity

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention changes the thermal expansion parameter by selecting a compliant attachment material with an intermediate coefficient of thermal expansion. This parameter optimization allows the compliant attachment to absorb thermal expansion mismatches and reduce interfacial strain between components with differing thermal properties

Inventive Principle:

Principle #35Parameter changes

2Reliability

If a compliant attachment with intermediate thermal expansion coefficient is added to mitigate thermal strain, then thermal strain and delamination are reduced, but the connection structure becomes more complex

Engineering Contradiction:

Improveinterface robustnessVSAvoidnumber of components

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The compliant attachment is designed as a flexible, thin component that bonds to the interfacing surface of the OMC body portion. Its flexible nature allows it to absorb thermal and mechanical strains while maintaining a compact structure that does not significantly increase overall device complexity

Inventive Principle:

Principle #30Flexible shells and thin films

3Strength

If traditional bonding methods are used to attach the compliant attachment, then the bonding process is simple, but the bond strength and durability may be insufficient under thermal and mechanical loading

Engineering Contradiction:

Improvebond strengthVSAvoidbonding process complexity

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

Transient liquid phase bonding and brazing methods utilize phase transitions (melting and solidification) to create strong, durable bonds between the compliant attachment and the OMC body portion. The bonding process involves heating to melt a filler metal or adhesive layer, then allowing it to solidify and form a robust joint that can withstand thermal and mechanical loading

Inventive Principle:

Principle #36Phase transitions

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 compliant attachment effectively reduces thermal or mechanical strain between OMC components and mating structures, improving the robustness and longevity of connections by transitioning thermal properties and absorbing expansion mismatches.

Implementation Method 1

mismatches in the coefficients of thermal expansion (CTE) between OMC components and their mating structures may cause thermal strain at the contact interfaces

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 2

bonded to the interfacing surface of the body portion by a bonding method selected from the group consisting of transient liquid phase bonding, partial transient liquid phase bonding, and brazing

Methodology Applied

Scientific EffectTransient liquid phase bonding:

Implementation Method 3

bonded to the interfacing surface of the body portion by a bonding method selected from the group consisting of transient liquid phase bonding, partial transient liquid phase bonding, and brazing

Methodology Applied

Scientific EffectBrazing: Brazing

Data Source

PatentUS10422234B2Compliant attachment for an organic matrix composite component

Publication Date: 2019.09.24 RTX CORP

AI summary

A compliant attachment for an organic matrix composite component that is configured to interface with a mating component is disclosed. The compliant attachment may comprise an inner surface configured to bond to an interfacing surface of a body portion of the organic matrix component, and an outer surface configured to interface with the mating component. The compliant attachment may have a coefficient of thermal expansion intermediate between a coefficient of thermal expansion of the body portion of the organic matrix composite component and a coefficient of thermal expansion of the mating component.