A ceramic yarn

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current knitting techniques fail to effectively incorporate ceramic fibers into knit fabrics due to their brittleness, leading to breakage during the knitting process, especially when forming complex geometries or near net-shape parts.

Innovation Solution

The use of a multi-component stranded yarn that includes a continuous ceramic strand wrapped around a load-relieving process aid strand, which alleviates overstress on the ceramic fibers during knitting, allowing for the formation of complex geometries and near net-shape performs without breakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If ceramic fibers are used to provide high tensile strength and high-temperature capability, then thermal protection performance is improved, but the fibers become prone to breakage under acute angle bends and small radius stress

Engineering Contradiction:
Improvehigh-temperature capabilityVSAvoidfiber breakage resistance
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent combines ceramic fibers with a flexible polymer matrix to form a composite yarn structure. The ceramic fibers provide high-temperature capability while the polymer matrix provides flexibility and prevents fiber breakage under stress. This composite approach allows the material to simultaneously achieve thermal protection performance and mechanical reliability.

Inventive Principle:
Principle #40Composite materials

2Productivity

If conventional machine sewing techniques are used to fabricate ceramic fiber articles, then productivity is improved, but the brittle ceramic fibers break during the sewing process

Engineering Contradiction:
Improvefabrication speedVSAvoidsewing processability
Core Design Contradiction:
ProductivityVSEase of manufacture

Solution Approach 1:

By embedding ceramic fibers in a flexible polymer matrix, the resulting composite yarn can be machine-sewn without fiber breakage. The polymer matrix absorbs the mechanical stress during sewing operations, enabling conventional high-speed manufacturing techniques to be used while maintaining fiber integrity.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The polymer matrix acts as an intermediary between the brittle ceramic fibers and the mechanical sewing process. It transfers and distributes the sewing stresses away from the ceramic fibers, preventing breakage while allowing machine fabrication to proceed at high productivity levels.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If hand sewing techniques are employed to avoid fiber breakage, then fiber integrity is maintained, but labor intensity and manufacturing time increase significantly

Engineering Contradiction:
Improvefiber integrityVSAvoidmanufacturing time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The composite yarn structure enables machine automation while maintaining fiber integrity. The polymer matrix protects ceramic fibers during high-speed machine handling and sewing, eliminating the need for slow hand sewing techniques while preserving fiber strength and continuity.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent replaces the need for gentle hand manipulation with a robust composite material that can withstand machine-level mechanical stresses. This substitution of material properties for process gentleness enables automation and dramatically reduces manufacturing time while maintaining fiber integrity.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

4Adaptability or versatility

If ceramic fiber fabrics are knitted into complex geometries, then design versatility is improved, but the fibers break due to small radius stresses in the knitting process

Engineering Contradiction:
Improvegeometry complexityVSAvoidfiber breakage resistance
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The flexible polymer matrix in the composite yarn allows the material to be knitted into complex three-dimensional geometries without fiber breakage. The matrix accommodates the small radius bends and deformations inherent in knitting complex shapes while protecting the ceramic fibers from tensile stresses that would cause breakage.

Inventive Principle:
Principle #40Composite materials

Data Source

PatentEP3712311B1A ceramic yarn
Publication Date: 2025.06.04 THE BOEING CO
  • EP3712311B1 patent drawingFigure 1
  • EP3712311B1 patent drawingFigure 2
  • EP3712311B1 patent drawingFigure 3

AI summary

Knit fabrics having ceramic strands, thermal protective members formed therefrom and to their methods of construction are disclosed. Methods for fabricating thermal protection using multiple materials which may be concurrently knit are also disclosed. This unique capability to knit high temperature ceramic fibers concurrently with a load-relieving process aid, such as an inorganic or organic material (e.g., metal alloy or polymer), both small diameter wires within the knit as well as large diameter wires which provide structural support and allow for the creation of near net-shape performs at production level speed. Additionally, ceramic insulation can also be integrated concurrently to provide increased thermal protection.