Co-molding Non-crimped Fabric with SMC

Solution Overview

Problem

Non-crimped fabric (NCF) is difficult to place in compression tools and tends to move during the compression molding process, leading to distortion and limited structural benefit in the laminate.

Innovation Solution

The method involves drying and pre-forming the NCF to stiffen it, and using tooling with thorns and ramps to lock the NCF in position during molding, preventing movement and distortion due to SMC flow.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If non-crimped fabric is placed in compression tool during compression molding, then the fabric can be molded into parts, but the fabric moves and distorts due to material flow

Engineering Contradiction:

Improveease of placing NCF in compression toolVSAvoidposition stability of NCF during molding

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The NCF is pre-formed into a three-dimensional configuration that matches the target part geometry before being placed in the compression tool. This preliminary shaping allows the fabric to be more easily positioned and reduces movement during molding, as the pre-formed structure naturally conforms to the desired final shape and resists displacement by material flow.

Inventive Principle:

Principle #10Preliminary action

2Strength

If non-crimped fabric is used in compression molding, then continuous fiber reinforcement is achieved, but the fabric gets distorted or torn apart due to SMC flow

Engineering Contradiction:

Improvestructural benefit of continuous fiberVSAvoidintegrity of fabric during molding

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The NCF is pre-formed into a three-dimensional configuration that matches the target part geometry before being placed in the compression tool. This preliminary shaping allows the fabric to be more easily positioned and reduces movement during molding, as the pre-formed structure naturally conforms to the desired final shape and resists displacement by material flow.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The compression molding process parameters are optimized to control the flow of SMC material. By adjusting parameters such as compression pressure, temperature, and molding speed, the material flow is controlled to minimize distortion and tearing of the NCF while still achieving complete impregnation and dense consolidation.

Inventive Principle:

Principle #35Parameter changes

3Quantity of substance

If SMC material flows during compression molding, then complete impregnation of NCF is achieved, but the NCF moves to shear edges and loses structural benefit

Engineering Contradiction:

Improveimpregnation completeness of NCFVSAvoidNCF position stability

Core Design Contradiction:

Quantity of substanceVSManufacturing precision

Solution Approach 1:

The NCF is pre-formed into a three-dimensional configuration that matches the target part geometry before being placed in the compression tool. This preliminary shaping allows the fabric to be more easily positioned and reduces movement during molding, as the pre-formed structure naturally conforms to the desired final shape and resists displacement by material flow.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The compression molding process parameters are optimized to control the flow of SMC material. By adjusting parameters such as compression pressure, temperature, and molding speed, the material flow is controlled to minimize distortion and tearing of the NCF while still achieving complete impregnation and dense consolidation.

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 approach allows for effective placement and retention of NCF during compression molding, ensuring full coverage and minimal movement, which enhances the structural integrity of the manufactured parts.

Implementation Method 1

the drying of the pre-preg (resin impregnated non crimped fabric, NCF) stiffens up the pre-preg thereby limiting the movement and distortion of the fabric

Methodology Applied

Scientific EffectDrying: Evaporation

Implementation Method 2

the drying of the pre-preg (resin impregnated non crimped fabric, NCF) stiffens up the pre-preg

Methodology Applied

Scientific EffectHeat treatment: Heat Treatment

Data Source

PatentUS12240192B2Co-molding of non-crimped fabric and SMC

Publication Date: 2025.03.04 MAGNA EXTERIORS INC

AI summary

Co-molding of non-crimped fabric and sheet molding composition. The pre-preg of non-crimped fabric is dried to achieve suitable stiffness for molding. The pre-preg allows the pre-formed non-crimped fabric feature to retain its shape during molding. A plurality of thorns is provided in the molding tooling to further prevent movement of pre-preg during molding. The method of co-molding includes, drying of the pre-preg to achieve suitable stiffness for molding, pre-forming of the pre-preg, and incorporating a plurality of stand-off features or thorns in the molding tool to prevent movement of pre-preg during co-molding so that predetermined full coverage of non-crimped fabric is maintained in predetermined area(s) of the molded part and the continuous fibers of the non-crimped fabric are not distorted.