Polymer towpreg for ceramic matrix composites

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Ceramic matrix composites face challenges in applying interface coatings due to the close packing of filaments in ceramic tows, leading to undesirable bridging and densification issues.

Innovation Solution

The method involves impregnating ceramic tows with a first polymer binder to increase filament-to-filament spacing, incorporating these tows into a ceramic fabric, and applying a second polymer binder solution to facilitate preform formation, followed by decomposition and interface coating deposition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If ceramic tows are tightly packed with hundreds of filaments, then the density and structural integrity of the composite is improved, but the application of interface coatings becomes difficult due to bridging and densification issues

Engineering Contradiction:

Improvestructural integrityVSAvoidinterface coating application

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The ceramic tow is segmented into individual filaments by introducing a polymer binder between them, creating spatial separation. This segmentation allows interface coatings to be applied uniformly to each filament without bridging, while the overall tow structure maintains its integrity through the binding action of the polymer.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A polymer binder is introduced as an intermediary substance between adjacent ceramic filaments. This intermediary increases the spacing between filaments, preventing direct contact and bridging during interface coating application, while still maintaining the tow's structural coherence.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of manufacture

If polymer binder is applied to increase filament spacing, then interface coating application is improved, but the complexity of the manufacturing process increases

Engineering Contradiction:

Improveinterface coating applicationVSAvoidmanufacturing process

Core Design Contradiction:

Ease of manufactureVSDevice complexity

Solution Approach 1:

The polymer binder is applied to the ceramic tows in advance, before the interface coating process. This preliminary action of impregnating the tows with binder solution and allowing it to dry creates the necessary filament spacing beforehand, simplifying the subsequent interface coating application without requiring complex real-time adjustments.

Inventive Principle:

Principle #10Preliminary action

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 approach allows for more uniform interface coating application and improved matrix infiltration, enhancing the toughness, durability, and performance of ceramic matrix composites.

Implementation Method 1

impregnating a plurality of individual ceramic tows with a first polymer binder

Methodology Applied

Scientific EffectAbsorption: Absorption (physical)

Implementation Method 2

applying a solution comprising a second polymer binder and a second solvent to the ceramic fabric

Methodology Applied

Scientific EffectDeposition: Deposition (physical)

Implementation Method 3

decomposing the first polymer binder and the second polymer binder

Methodology Applied

Scientific EffectDecomposition: Decomposition (biological)

Data Source

PatentUS20250066260A1Polymer towpreg for ceramic matrix composites

Publication Date: 2025.02.27 RTX CORP

AI summary

A method of fabricating a fibrous ceramic preform includes impregnating a plurality of individual ceramic tows with a first polymer binder, incorporating the plurality of impregnated ceramic tows into a ceramic fabric, applying a solution comprising a second polymer binder and a second solvent to the ceramic fabric, and incorporating the ceramic fabric into the preform. The first polymer binder is insoluble in the second solvent.