high volume manufacturing of carbon fiber reinforced...
TRANSCRIPT
16.05.2017 - Materialien des Karosseriebaus, Bad Nauheim
David Roquette, Dr. Florian Meyer - AUDI AG
Dr. Lars Herbeck - Voith Composites GmbH & Co. KG
High Volume Manufacturing of
Carbon Fiber Reinforced Plastics for Body in White
› Global and Automotive Trends
› Projects and Aims for the Introduction of CFRP
› Technology Development Carbon Rear Wall
› Realization at Voith Composites
› Conclusion
Content
Global Trends - Challenge for the Automotive Industry
Regulations
Emissions and Electrification
Individualisation
Sustainability
Digitalisation
Smart Connect
Automotive Trends - Challenge: Weight Increasing Factors
► Innovations and comfort- e.g. for self driving concepts
► Safety requirements
► CO2 emissions – e. g. electrification of power train (PHEV, BEV, …)
► Legislation (NOX, Ad Blue…)
► Country specific regulations
Density of steel, aluminum, carbon fiber reinforced plastics (CFRP)
approx. 5:2:1
Costs
approx. 2:10:50
Weight reduction potential in body applications
approx. 100:70:60
Efficient weight reduction (€/kg) as the aim for the Audi Multimaterial Space Frame.
The right material at the right place in the right amount
Typical Materials for Body in White
7,8
2,7 1,5
Density
[kg/dm³]
2
4
6
8
10
0 Steel CFRP Aluminium
Steel
Normalized
car-body
weight[%]
100
0 Steel Aluminium CFRP
Aluminium CFRP Steel
Cost
[€/kg]
0
Bugatti Veyron
First-time evidence Class-A
LB Gallardo Spyder
Class-A evidence with large, horizontal
component
R8 Coupé predecessor
Sideblade with visible-CFRP
R8 Spyder predecessorNumber of
units 20/day Class-A CFRP
RS3 Number of
units 40/day Class-A CFRP
R8 e-tron CFRP in structure
CFRP in crash area
New Audi R8 /
Lamborghini Huracán
Number of units 45/day CFRP in
structure Standardization
CFRP in structure Cost reduction
with high number of units
New A8 Number of units
150-300/day Industrialization
tech
no
log
ica
l le
ve
l
Class-A in RTM with large
component
Visible CFRP in RTM
Complex geometry
Number of units
Maximization of lightweight
potential
CFRP in structure Cost reduction
Class-A in RTM
timeline
Projects and Aims for the Introduction of CFRP
1st step: development of basic technology Class-A and visible-CFRP
2nd step: built up competence for high volume
3rd step: cost reduction and integral design
Breakthrough technologies are developed at the Audi Lightweight Center and
transferred with potential suppliers to serial production.
Material and Process Development for Large Structures with Integral Design
2012 2014 2015
R8 (MSS) Coupé
Differential Design
Predevelopment Project
R8 (MSS) Coupé Integral Design
2013
R8 (MSS) Spyder
Integral rearwall and B-pillar
R8 Prototypes
R8 (MSS) Spyder Integral Design
2016 2017
Approach and Realization: Integral Design and High Volume
3rd step: cost reduction and integral design
2nd step: built up competence for high volume
A8 (D5)
Integral Design High Volume
Carbon Rear Wall
A8 Prototypes (D5)
CFRP in the Audi R8 and the New Audi A8 - Multimaterial Audi Space Frame
Audi R8 Coupé and Spyder
Modular Sportscar System (MSS) New Audi A8
Small Series to
High Volume
› Single part reduction and integration of function due to an integral design
› Preassembled module within assembly line
› Highly anisotropic layup with localized load paths
1
2
Necessary Steps in Technology Development from R8 to A8
Appropiate composite-based design
Materials & Technology
› Cost efficient Composite Solution Package (Carbon Fiber, Resin & Adhesive)
› New Ultra-RTM Technology (low mould pressure/ robust process / short cycle-time )
› Innovative direct fiber placement technology (reduced scrap & optimized layup)
› Highly automated and linked manufacturing process
Carbon Rear Wall Structure - Functional Integration
Density
-45%
1
D4 – Current A8
D5 – New A8
Weight
-50%
D4 D5 D4 D5
Single part reduction and integration of functions are realized due to an integral design.
Preassembly of several components parallel to assembly line.
Carbon Rear Wall - Maximizing Anisotropy 1
Minimum use of carbon fiber due to highly anisotropic layup with localized load paths.
Highlights
› 6-19 optimized layers
› High variety in part thickness:
1.5 / 1.7 / 2.5 / 2.7 / 3.7 mm
› 30% of static torsional stiffness are
related to the carbon rear wall
Materials - Efficient Composite Solution Package 2
Carbon Fiber
Zoltek Panex PX35
• Zoltek PX35 50k large tow fiber
• Optimized balance of performance and
costs for high volume applications
• Long term price commitment
up to 7 years
• Textile Type PAN based precursor
• Stability of Supply
Resin & Internal Mould Release
VORAFORCETM 5300 - Epoxy RTM
• Curing time 90-120s @120°C
• Open - Cure time ratio 1:2
• Processing viscosity <20mPas
• Latent reaction behavior
• Effective mold release
• Excellent fiber adhesion
• No post cure required
• High machine compatibility
Adhesive
BETAFORCETM 9050M
• Used for metal inserts and assembly
• Compatible with VORAFORCETM & IMR
• Pretreatment-free adhesion
• heat accelerated cure and ambient
temperature latency
• Multi material mix – Da management
(high elongation and stiffness)
price-performance ratio for tensile properties
Composite stiffness GPa/€
Co
mp
osi
te s
tre
ng
th M
Pa
/€
performance
automotive fibre low-cost
automotive fibre
Source: Dow Automotive Systems Source: Dow Automotive Systems
Large Parts
Low Pressure
Fast Injection
Technology and Process - ultra-RTM D5 Prototype 2
Standard-HP-RTM:
„pick only two“
Main challenge: Infiltration of complex parts with ultra-fast-cure resins and very low cavity
pressure could be solved by innovative process controlled injection and press step.
Ultra-RTM
Fibre clamping resin stops at clamping, no resin sealing needed
Resin Shot weight: 1.3 kg
Sprue: point injection, no resin channel
Mass flow: 130 g/s
Time press
open to open: <180 s
RTM-tool bottom side RTM-tool with dry preform Cured part before demoulding Dry fibers outside clamping
ultra-RTM technology can produce the same quality with smaller, efficient hydraulic presses
and a very robust process also for high fiber volume content (50-55%).
Technology and Process - ultra-RTM D5 Prototype 2
0
5000
10000
15000
20000
25000
0 05 10 15 20 25 30 35
forc
e [
KN
]
time [s]
0,0
0,2
0,4
0,6
0,8
1,0
0 05 10 15 20 25 30 35
ga
p h
eig
ht
[mm
]
time [s]
0
20
40
60
80
100
120
140
0 05 10 15 20 25 30 35
pre
ssu
re [
ba
r]
time [s]
Injection Compression Curing
In Mould Pressure During Injection
Press Force During Process
Gap Height During Process
130 g/s
65 g/s
>130 g/s
En
d o
f in
ject
ion
En
d o
f co
mp
ress
ion
HP-RTM „classic“
Advanced RTM
ultra-RTM
2500t Press Force
350t Press Force
Technology Transfer to Serial Production
Breakthrough technologies are developed at the Audi Lightweight Center and
transferred with Voith Composite to serial production.
Voith Composites
From Fiber Straight to Component
… manual processing
Yesterday ... Today …
… automated processing
Elimination of expensive semi-finished products, reduction of cycle time due to elimination of
process steps, completely digitalized production based on “Carbon Production 4.0“
16
Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 17
Industrialized Process Chain CFRP Rear Wall Audi A8
Materials Assembly Semi finished Preforming Consolidation Milling
Mostly industrialized Mostly industrialized Manufacture
Sta
nd
ard
Materials Preforming Consolidation
Industrialized Production
Assembly Milling
Le
an
Fiber Placement (VRA)
3D Forming 3D Cutting Ultra RTM Process
CNC Milling Surface Cleaning
Riveting & Bonding
Fiber & Binder Resin Metallic Attachment Parts
De
tails
Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 18
Process Chain Step: Voith Roving Applicator (VRA)
Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly
• Industrialized production line
• Near net shape fiber placement
• Automated quality control
• Fully digitalized
• Flexible 2D fiber layup
• Variable fiber angle
Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 19
Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly
Process Chain Step: 3D Forming
• Segmented stamp forming
• Complete automated handling
• Forming process 2D 3D
• Activation of binder
• Tailored Preforms
• Stabil in RTM process
Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 20
Process Chain Step: Injection & Consolidation Ultra RTM
Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly
• Fully industrialized process
• High production rate
• Curing time < 120 s.
• Low injection pressure
• Optimal surface quality
• No fiber washing
Voith Composites | Bad Nauheim Materialien des Karosseriebaus | 16. Mai 2017 | confidential 21
Process Chain Step: Riveting and Bonding of Metallic Parts
Fiber Placement 3D Forming 3D Cutting Ultra RTM CNC Milling Cleaning Assembly
• Surface cleaning with water
• No mechanical treatment for
bonding necessary
• Fully automated bonding
• Fast curing 2k PU System
• Automated riveting
• Riveting force documentation
› The new A8 CFRP Rear Wall has a weight reduction of 50% compared to the current A8.
› Breakthrough technologies have been developed at the Audi Lightweight Center and together with Voith Composites transferred to serial production.
› Due to the new developed technologies it is possible for the first time to use the full potential of CFRP within high volume.
› Lean production: Voith Roving Applicator for elimination of semi finished products
› Industrialization: mechanization and automation of processes
Conclusion
TechDay Body Structure
Thank you