Composite Parts with Continuous and Chopped Fiber Co-Curing

Solution Overview

Problem

Chopped fiber composite parts exhibit reduced structural strength and rough surfaces, making them undesirable for applications like aerospace due to increased drag and suboptimal electromagnetic properties.

Innovation Solution

The integration of layers of continuous fibers oriented in parallel with a mass of chopped fibers, where the continuous fiber layers form the exterior surfaces and are co-cured with the chopped fibers to create a composite part with improved surface properties and structural integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If chopped fiber is used to fabricate composite parts, then manufacturing cost is reduced and labor intensity is decreased, but structural strength and surface smoothness deteriorate

Engineering Contradiction:

Improvemanufacturing cost and labor intensityVSAvoidstructural strength

Core Design Contradiction:

Ease of manufactureVSStrength

Solution Approach 1:

The patent applies local quality by using different fiber types in different regions of the composite part. Chopped fibers are used in the core region where cost-effectiveness is prioritized, while continuous fibers are applied at exterior surfaces where structural strength and surface smoothness are critical. This spatial differentiation of material properties resolves the contradiction between manufacturing ease and structural strength.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent creates a hybrid composite material system combining chopped fibers and continuous fibers in a single structure. The chopped fibers provide cost-effective bulk reinforcement while continuous fibers provide high-strength surface layers. This composite approach allows the part to simultaneously achieve low manufacturing cost and high structural strength by leveraging the complementary properties of different fiber types.

Inventive Principle:

Principle #40Composite materials

2Ease of manufacture

If chopped fiber is used to fabricate composite parts, then manufacturing cost is reduced and labor intensity is decreased, but surface smoothness deteriorates

Engineering Contradiction:

Improvemanufacturing cost and labor intensityVSAvoidsurface smoothness

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent applies local quality by using different fiber types in different regions of the composite part. Chopped fibers are used in the core region where cost-effectiveness is prioritized, while continuous fibers are applied at exterior surfaces where structural strength and surface smoothness are critical. This spatial differentiation of material properties resolves the contradiction between manufacturing ease and surface smoothness.

Inventive Principle:

Principle #3Local quality

3Quantity of substance

If chopped fiber is used to fabricate composite parts, then material cost is reduced, but aerodynamic performance deteriorates due to increased drag

Engineering Contradiction:

Improvematerial costVSAvoidaerodynamic drag

Core Design Contradiction:

Quantity of substanceVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by using different fiber types in different regions of the composite part. Chopped fibers are used in the core region where cost-effectiveness is prioritized, while continuous fibers are applied at exterior surfaces where structural strength and surface smoothness are critical. This spatial differentiation of material properties resolves the contradiction between manufacturing ease and surface smoothness.

Inventive Principle:

Principle #3Local quality

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 results in composite parts with enhanced surface smoothness, reduced drag, and improved structural strength, while allowing for the use of a large amount of chopped fibers, thus addressing the limitations of traditional chopped fiber composites.

Implementation Method 1

curing the chopped fibers and the laminate together into an integral composite part

Methodology Applied

Scientific EffectCuring:

Data Source

PatentUS10933598B2Fabrication of composite parts having both continuous and chopped fiber components

Publication Date: 2021.03.02 THE BOEING CO

AI summary

Systems and methods are provided for fabricating composite parts that include both chopped fiber and continuous fiber components. One embodiment is a method that includes laying up a laminate comprising at least one ply of continuous fiber-reinforced polymer onto a first surface of a mold, filling a cavity of the mold with chopped fibers and resin that contact the laminate, curing the chopped fibers and the laminate together into an integral composite part, and separating the integral composite part from the mold.