3D woven spacer fabrics in sports applications

–

Glass fiber reinforced snowboards

Conference „Composites without borders“, Moscow

…

Stefan Fenske, Benedikt Wendland, Marcel Haeske, Thomas Gries

Institut für Textiltechnik der RWTH Aachen University (ITA), Aachen, Germany

16.10.2014

Reference:

http://upload.wikimedia.org/wikipedia/commons/2/23/

Snowboard_saut_et_tremplin.jpg

www.globaltextiles.com

1) Presentation of the ITA

2) Motivation

3) 3D woven spacer fabrics – an introduction

4) Materials and methods

5) Results & Conclusion

6) Outlook

Outline

2 Reference:

http://upload.wikimedia.org/wikipedia/commons/2/23/

Snowboard_saut_et_tremplin.jpg

www.globaltextiles.com

1) Presentation of the ITA

2) Motivation

3) 3D woven spacer fabrics – an introduction

4) Materials and methods

5) Results & Conclusion

6) Outlook

Outline

3

ap

plic

ati

on

fie

lds

mobility

building &

living

health

energy

Comprehensive textile

process chains

technology and

competence fields

raw

mate

rials

:

natu

ral fi

bers

, p

oly

mers

,...

sem

i-fi

nis

hed

texti

les &

pro

du

cts

The unique position of ITA

4

Budget: ca. 14,3 Mio. €

Staff:

100 Scientists

55 Service personnel

190 Graduate research assistants

50 Students majoring in textile

technology each year

Research and development

Publicity and third party

funded research

Academic and industrial education

Development and transfer

Direct industrial research

Further education

partially public p

ub

lic

Str

ictly c

onfidential Fundamental

Research

ca. 30%

Industrial Funding

ca. 31%

Industry-Related

Public Funding

ca. 35%

Subsidy

ca. 4%

ITA – Facts and Figures

5

1) Presentation of the ITA

2) Motivation

3) 3D woven spacer fabrics – an introduction

4) Materials and methods

5) Results & Conclusion

6) Outlook

Outline

6

Motivation

Typical Snowboard Build-Up

7 Source: www.allstaractivities.com

Snowboarding is very popular

New snowboard technologies can be a very lucrative market!

State of the art in snowboard construction: many different layers, often with a wooden core

High demand of lightweight snowboards, fabricated in an automated production process

Motivation

Snowboard materials are required to withstand high mechanical tensions and forces

Glass fibers exhibit appropriate mechanical properties

Objective:

Production of a snowboard

made of glass fiber reinforced plastics (GFRP)

with a 3D woven spacer fabric as textile structure

3D woven spacer fabric

8 Source: www.parabeam.nl

1) Presentation of the ITA

2) Motivation

3) 3D woven spacer fabrics – an introduction

4) Materials and methods

5) Results & Conclusion

6) Outlook

Outline

9

Consist of two or more orthogonal

intersected yarn systems:

Warp yarns

Weft yarns

5000 years old principle

Total production: approx. 30 million

tons woven fabrics/year

Advantages for reinforcement

applications

Cost-effective manufacturing

High reproducibility

Good process-ability

Excellent formability

Woven fabrics - Overview

Plain Weave Twill Weave Satin Weave

10

Classification of 3D woven fabrics

3D - woven fabrics

Integral fabrics Distance fabrics Hollow cellular

fabrics Circular and

tubular woven fabrics

Contour fabrics Hybrid woven/knitted

fabrics

Multilayer fabrics

3D - orthogonal -

fabrics

3D - woven

3D - fabrics

Distance fabrics with interlocking

yarns

Distance fabrics with plane interlocking

3D - contour weaving method

Contour fabrics on conventional

weaving looms

Circular weaving Multiaxial 3D orthogonal

circular weaving

Tubular nodal fabrics

Tubular fabrics Multiaxial

fabrics

11

3D woven spacer fabrics – specifics

Pile yarns

Weft yarn

Warp yarn

Production direction

Weft direction Warp direction

Additional yarns in the z-direction

Good compression characteristics

due to pile yarns

Mechanical properties can be

adjusted by changing the pile

binding and outer structures

Machinery requirements include a

simultaneous multiple weft

insertion and an adjusted

shedding system

Main applications are structural

composites and cushioning

Not suitable for carbon in the z-

direction

12

Production of 3D woven spacer fabrics

Double Rapier

Weft yarn

Warp yarn

Pile yarns

Warp healds

Pile healds

Principle of carpet weaving,

but without cutting of the

pile yarns

Two separate sheds are

formed to produce two

ground fabrics

one at the top and one

at the bottom

Two weft shots are inserted

simultaneously by rapiers

13

1) Presentation of the ITA

2) Motivation

3) 3D woven spacer fabrics – an introduction

4) Materials and methods

5) Results & Conclusion

6) Outlook

Outline

14

Materials

Specification spacer fabrics:

Warp direction: E-Glass 136 tex, 10 threads/cm

Weft direction: E-Glass 136 tex, 10 threads/cm

Pile direction: E-Glass 68 tex, 50 connections/cm²

Insert with screw thread

Cut spacer fabric Cut pile yarns

Metal insert integration by

cutting the spacer fabric and a

portion of pile yarns

15

Methods

Production with manual hand lay-up

Not possible to apply pressure

to pile yarns of spacer fabrics

Production of two series of

materials for insert pull-out tests

1st NCF on bottom in order to

increase mechanical stability

2nd NCF on top in order to protect

the weakened area where the insert

is put in

Spacer fabric

Spacer fabric

NCF at

bottom

NCF at

bottom

NCF on top

1st series: Non-Crimp Fabric (NCF) only at the bottom

2nd series: Reinforcing NCF at bottom and on top

Weft direction Warp direction

16

Methods

Insert pull-out tests conducted

according to DIN ISO 10958-2

Test direction: warp

Since variation of pile yarn height

is only possible in said direction

Bottom plate

Top traverse

Sample with insert Bearing roll

Universal Testing Machine

17

1) Presentation of the ITA

2) Motivation

3) 3D woven spacer fabrics – an introduction

4) Materials and methods

5) Results & Conclusion

6) Outlook

Outline

18

Results

0

500

1000

1500

2000

2500

0 10 20 30 40 50

Fo

rce

[N

]

Displacement [mm]

1.Serie

2.Serie

Maximum pull-out force is about

2000 N

Shear strength in the pile yarn

area is low.

Failure happens in pile yarn area! Failure of pile yarns Failure of pile yarns

19

Conclusion

Production of composites is challenging

Parallelism between ground fabrics difficult to achieve with hand lay-up

Pile yarn configuration not well suited for pull-out tests

Weak spot identified!

20

1) Presentation of the ITA

2) Motivation

3) 3D woven spacer fabrics – an introduction

4) Materials and methods

5) Results & Conclusion

6) Outlook

Outline

21

Outlook

Production of the composites needs to be improved

Combination of spacer fabric with foam core to increase stability

Automation of the infusion process

Shear strength can be improved by variation of pile yarn set-up

Integration of the metal inserts needs to be improved

Weakening of spacer fabric by manual insert integration

Development of automated insert integration

Additional pile yarns

in 45°-direction

Increased pile

yarn density

Distance fabric

22

Dipl.-Ing. Stefan Fenske

Department of Composites

Phone: +49 (0)241 80 247 53

Fax: +49 (0)241 80 224 22

E-Mail: stefan.fenske@ita.rwth-aachen.de

Contact details

Thank you for your attention!

23