COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

CURRENT JAPANESE ACTIVITY IN CFRTP FOR INDUSTRIAL APPLICATION

Jun Takahashi1* and Takashi Ishikawa2 1 The University of Tokyo, Professor 2 Nagoya University, Professor

* corresponding author: takahashi-jun@cfrtp.t.u-tokyo.ac.jp

ABSTRACT

Japanese CFRTP researches are going to rush into the next stage. Some research centers for CFRTP were established in the past few years, and new national project aiming to pursue multifunctional and ultra-lightweight automobile (2013-2022fy) started. This paper introduces such current Japanese activities.

WHAT IS HAPPENING IN JAPAN?

The University of Tokyo has organized Japanese national project to develop CFRTP for mass production automobile from 2008 to 2012fy [1]. In a meanwhile, a lot of groups which are interested in CFRP have been appeared as shown in Figure 1, and among them research centers for composite materials, in especially for CFRTP, have been established in the only past few years as shown in Table 1.

The background of this bubbly investment is sure to be the awareness of automotive manufacturers. They have applied ultra-lightweight technology only to the special automobile to supply extreme driving performance, but nowadays they have faced to the social demand for developing mass production electric vehicle and ultra-lightweight vehicle to mitigate the global oil consumption and CO2 emission (see Table 2). Simultaneously, they have to adapt new social demand such as personal vehicle and more and more safety vehicle. For example, US-IIHS (insurance institute for highway safety) is going to ask automotive company to make automobile safer in the case of 25% offset front collision. It does not only make automobile heavier, but also will force automotive structure to change.

Therefore, new Japanese national project (2013-2022fy) started to develop technologies that can make us respond quickly to such demands of design changes, and pursue multifunctional and ultra-lightweight automobile by using CFRTP (see Figure 2). Including 3 CF manufacturers (Toray, Toho Tenax and Mitsubishi Rayon whose total world CF production share is about 60% as shown in Figure 3) and 5 automobile companies (Toyota, Nissan, Honda, Suzuki and Mitsubishi Motors whose total world passenger automobile production share is about 27% as shown in Figure 4), 22 companies, 5 public institutes and 7 universities participate in this project. While materials, structure and manufacturing techniques are going to be developed, wide range of CAE technologies are also going to be developed concerning material design, structural design and molding simulation (see Figure 5).

PURPOSE OF THE NEW NATIONAL PROJECT

The former national project has verified the potential of CFRTP whether the cost target of passenger automobile shown in Figure 6 can be achieved or not. Hence we have focused on the material development and high-cycle molding/welding while making clear their

COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

mechanisms (see Figures 7-16 and Table 3). Based on the results, the new national project is aiming to develop the following technologies.

(1) Design by/of CFRTP:

The former project has verified the applicability of CFRTP by making individual automotive parts with the same shape of steel ones as shown in Figure 15. But it is obviously not the best way of CFRTP usage. Hence structural design for both multi-materials and all-composite automobiles will be investigated in the new project. And new materials will be developed by the requests from design and manufacturing groups as shown in Figure 5.

(2) High-cycle manufacturing:

The former project has individually investigated resin impregnation, parts molding and their welding, but the new project will aim to find an integrated optimal manufacturing process applicable to factory production.

(3) Market waste recycling:

The former project developed some ways to make automotive parts by using in-plant CFRTP waste, but the new project will find the way to make automotive parts by using market CFRTP waste (see Figure 16).

REFERENCES

1. J. Takahashi, K. Uzawa and T. Matsuo, “Strategies and Technological Challenges for Realizing Lightweight Mass Production Automobile by using CFRTP”, Proceedings of JISSE12, No.PL-3, (2011-11).

Tohoku2 Aomori5 Akita

Kanto10 Gunma11 Saitama13 Tokyo … LCIC

Chubu15 Niigata17 Ishikawa … ICC18 Fukui21 Gifu … GCC22 Shizuoka23 Aichi … NCC

Kinki (Kansai) Chugoku

34 Hiroshima35 Yamaguchi

Shikoku36 Tokushima38 Ehime

Kyushu40 Fukuoka

Figure 1 Japanese regions and prefectures promoting CFRP.

COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

Table 1 Recent established Japanese research centers for composite materials.

Since Name Full name Location Key persons

2009July

LCICLow Carbon Engineering 

Innovation CenterThe University of 

TokyoKazuro KageyamaJun Takahashi

2012April

NCC National Composite Center Nagoya University Takashi Ishikawa

2012April

GCCGifu University Composite 

Materials CenterGifu University

Takushi MiyakeAsami Nakai

2012August

ICCIshikawa Carbon Fiber 

ClusterKanazawa Institute 

of TechnologyIsao KimparaKiyoshi Uzawa

Table 2 Expectations for CFRTP (similarities and differences between airplane and automotive application).

Airplane Automobile

Motivation high oil price→  ght na onal budget 

(including military budget)

→ low‐cost CFRP (<50€/kg)and maintenance

high oil prices and CO2 measures→ weight lightening & early spread

of EV (by battery reduction)

→ low‐cost CFRP (<10€) and recycling

Directionof technology development

Material& Preform low‐cost engineering plastics

low‐cost & productive CFlow‐cost general‐purpose resinlow‐cost impregnation

Molding low‐cost manufacturing→from hours to minutes→thermoforming/welding

yield improvement→automatic tape placement

measures for labor costs and intellectual property

→ automa on

low‐cost manufacturing→less than one minute→thermoforming/welding

yield improvement→recycling of in‐plant waste

measures for labor costs and intellectual property

→ automa on

Operation repairabilityimpact resistancesimplification of NDI

repairabilityrecyclability of market wastenew design for dynamic social demand

2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020

CFRTP (structure) Project (2013‐2022) Composite design High cycle manufacturingMarket waste recycling

METI, +25 (+9)PL: Prof. Takahashi (LCIC), Prof. Ishikawa (NCC)

LCIC, NCC, ICC, Tokyo Institute of Tech., Fukui Pref., JFCC, NIMS, Mitsubishi Rayon, Toho Tenax, Toray, Toyobo, Shimadzu, Aisin Seiki, Fukui Fibertech, KADO Corporation, Komatsu, Kyowa, Takagi Seiko, IHI, SHI, Honda, Mitsubishi Motors, Nissan, Suzuki, Toyota, (GCC, Tohoku Uni., Yamagata Uni., AIST, JAXA, DOME, Meiki, Taiseiplas, Toray Engineering)

Innovative CF Project Productive & low cost

METI, +5GM: Prof. Kageyama, PL: Prof. Hatori (LCIC)

LCIC, AIST, Mitsubishi Rayon, Teijin, Toray

CFRTP (material) Project Parts replacement High cycle molding In‐plant waste recycling

METI, NEDO, +5 (+5)PL: Prof. Takahashi (LCIC)

LCIC, Mitsubishi Rayon, Toray, Toyobo, Takagi Seiko

(Kyoto Institute of Tech., Shizuoka Uni., Tohoku Uni., Toyama Uni., Yamagata Uni.)

Figure 2 Japanese national projects for mass production CFRP automobile.

COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

Consumptionby region

Productionvolume

Productioncapacity

Japan Western China Others

Figure 3 World carbon fiber share by production and consumption (2012).

Japan30%

Gremany19%USA

16%

Korea10%

France9%

China8%

Others8%

World production shareToyota 11%Nissan 6%Honda 5%Suzuki 4%Mazda 2%

Mitsubishi 2%Subaru 1%

Figure 4 World passenger automobile production share by country (2011).

merchantability

material simulation molding simulation CAE

mechanism of forming and flow behavior due to T‐p‐t, etc.

mechanism of physical property due to resin, fiber morphology, surface treatment, etc.

Usual development

know‐how aboutparts shape,molding condition, etc.

← demand for materials ← demand for shape

specification change

↓material 

modification↓

↑individual design by company

↑dynamic social 

demand

know‐how aboutevaluation method, properties DB, etc.

know‐how about performance, function, etc.

Figure 5 Systematic research and development of CFRTP technologies

for mass production automobile in LCIC and NCC.

COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

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Parts Cost  (yen/kg)

Parts Cost  (yen/kg)

Parts Cost  (yen/kg)

Parts Cost  (yen/kg)

Molding Cycle Time (minutes) CF Cost (yen/kg)

Effective Usage Ratio of CF (%) Volume Fraction of CF (%)

LaborOperationConstructionConsumptionMachineResinCF

Figure 6 Effective cost reduction methods of CFRTP parts.

Normal CF+ PP without modification

Normal CF+ PP with modification

Special treated CF+ PP without modification

Special treated CF+ PP with modification

Figure 7 Modification of both CF and PP to improve adhesion.

Weak interface

Strong interface (brittle resin)

Strong interface (ductile resin)

Debonding

Load

Cleavage crackpropagation

CF

Resin Load

Load

These phenomena lead tomacroscopic delamination=  reduction of sectional area (EI ∝Et3)

Thus, composites become easier to buckle by compressive load anddeform by flexural load

Load

Deformation

Shear fractureof resin

Figure 8 Difference in fracture process of composite materials.

COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

Table 3 Differences in jointed and curved section between CFRTS and CFRTP.

Thermosetting CFRP Thermoplastic CFRP

Bonding joints

Adhesive joint× disassembly○ workability△ reliability

→ facility become larger due to the integrated molding

Welding joint△ disassembly○ affordable, easy, fast (a few seconds)○ joint section is stronger than base material

→ mold small parts affordably, and assembly by welding joint technique !!

Bolted joints

○ disassembly× delamination when drilling× fiber cut, stress 

concentration

→ measures like metal insert→ increase in weight, 

manufacturing time, and cost

○ disassembly○ no delamination when drilling△ fiber is cut, stress is concentrated, but 

fracture is ductile

→ measures like insert are not necessary→ reduction in weight, manufacturing time, 

and cost → applicable to joints with metal, and reliable 

parts

Curved section 

× measures for stress concentration and delamination are necessary

→ structure becomes thick, complex and heavy

○ design is similar to metal○ possibility of new high cycle molding 

methods utilizing the high workability

→ structure becomes simpler, lighter‐weight, and affordable !!

PM

One shot

PM

IM

Combination

Stiffness Strength

Formability,   Molding Cycle Time,   Cost

Autoclave moldingwith

continuous prepreg

Press moldingwith

discontinuouslong fiber

Thermosetting

Thermoplasitcs

Injection moldingwith

discontinuous short fiber

Resin transfer moldingwith

continuous preform

→Too expensiveToo slowOnly simple shapeDifficult to recycle

↓Too weak

Energy Absorptance

High cycle press moldingwith discontinuous

thermoplastic prepregs

Fully resin impregnated preforms realize high cycle molding and high performance

Fiber/tape flow molding can make complex shape parts by one shot

Fibers keep straight and lengths keep longer than critical ones

Figure 9 Developing direction of CFRTP for mass production.

ThermoplasticsCarbon Fiber Press in 1 minPre heat

Isotropic preform

Isotropic preform technology

Cut

Impregnation

Dispersion

High cycle press molding

* It has been developed by Toray and Takagi Seiko.

Figure 10 Discontinuous CF reinforced thermoplastics prepreg sheet.

COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

High cycle press molding

Braiding

Cross sheet

Thermoplastic

Carbon fiber

High cycle bladder molding

Intermediate substrate

Primary parts

Final parts

Prepreg tape

UD sheet

Random sheet

Raw materials

Random

UD + random

Seamless pipe

Pipe made by welding

Impregnation

Plate with stiffeners

* It has been developed by Mitsubishi Rayon and Toyobo.

Figure 11 Continuous CF reinforced UD-tape and its various applications.

Panel with the same flexural stiffness

Panel with the same tensile stiffness

Hollow beam with the same flexural stiffness

Figure 12 Several comparisons of weight lightening ratio between CF/PP and steel parts.

Weight is 50% Shock absorption capacity is 

2.0 times of 440MPa grade steel1.5 times of 780MPa grade steel

Figure 13 Comparison between CFRTP and steel hollow beam with the same flexural stiffness.

COMPOSITES WEEK @ LEUVEN AND TEXCOMP-11 CONFERENCE. 16-20 SEPTEMBER 2013, LEUVEN

< Monocoque body >Better structure for lightweight

panel88%

frame12%

panel57%

frame30%

casting13%

< Frame monocoque hybrid body >Better for safety and recyclability

Automobile parts are mostly composed of plates.  Flexural properties are dominant in the case of 

automotive materials and structures.

Figure 14 Automotive materials and structures.

Body weight can be reduced by 30% with CFRTP application

0

500

1,000

1,500

Conventional CFRP car

車体

重量

（kg

）

CFRP

Others

AL

Steel

Standard sedanCFRP

Body weight1380→970kg （▲30%）

CFRP ： 17%(174 kg)

Steel968kg Steel

385kg

Continuous CFRTP：Structural member such as frame

Discontinuous isotropic CFRTP： Panels, complex parts

SeatDoor Frame

FR Engine Cover

Under Cover

Radiator Core Support

Fender SupportFront Cowl

Energy AbsorptionPipe

RR luggage space

RR luggage Partition

FR Dash

Door inner

Hood Roof

Vehicle weight (kg)

◆ Conventional car and CFRP car

Figure 15 Weight reduction concept by parts replacement using CFRTP.

“in-plant waste” : identity of the material is clearno environmental degradation

“market waste” : identity of the material is not clearwith environmental degradation

high quality recycled materials

NG partsWaste

In‐plant waste Market waste

Damaged parts

CF

Resin

Preform Primary parts Parts End of life parts

Figure 16 Difference between “in-plant waste” and “market waste”.