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www.acmashow.or
g
Thermoplastic Composites
and Processes
Klaus F. Gleich
Senior Research Associate,Johns Manville Technical Center
www.acmashow.org
February 21-23, 2012 Mandalay Bay Convention Center, Las Vegas, NV
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Overview
Introduction into Thermoplastic Fiber Composites
Semi-Finished Materials
Manufacturing Processes
Economics
Applications
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Introduction
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Specfic Tensile Properties of Polymer Matrix Composites
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 1 2 3 4 5 6
Specific Strength (x106 in.)
SpecificModulus(x108i
n.)
Metals
Continuous Uni-
directional Carbon
Composites
LFT Glass
Composites
Continuous Uni-directional
Glass Composites
LFT CarbonComposites
Plastics
Glass & Carbon
LFT & Continuous
Other Fibers
Varying Fiber Orientations
Why Use Composite Materials ?
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One Reason For Using Composites
Charlestown Bridge Boston
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Thermoplastic Composites
Benefits
Unique properties
Vibration dampening
Light weight
Potential for low cost
Shelf life
Recyclable
DurabilityFatigue
Corrosion
Toughness
Limitations
CostMaterials
Manufacturing
Tooling
Design know-how
Manufacturing know-how
Use temperature
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Thermoplastic Composites
Many Polymer Options
Polyethylenes
Polypropylenes
Nylons
Polycarbonates
Acrylics
Polyesters
PolyimidesPolysulfones
Polyketones
Polyurethanes
the list continues
Many Property Options
ultimate strain > 100%no micro cracking
no delamination
dampening
no water uptake
low dielectric propertiesmelt formable
weldable
elastomeric - plastic - elastic behavior
the list continues
Thermoplastic composites can be tailored to meet the
required properties.
Fiber Options
Glass FiberCarbon Fiber
Natural Fiber
Polymer Fiber
Stainless Steel Fiber
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Basic Properties of Fibers and other
Engineering Materials
Material Type Tensile Strenght Tensile Modulus Typical Density Specific Modulus
(MPa) (GPa) (g/cm3) (GPa)
Carbon HS 3500 160 - 270 1.8 90 - 150
Carbon IM 5300 270 - 325 1.8 150 - 180
Carbon HM 3500 325 - 440 1.8 180 - 240
Carbon UHM 2000 440+ 2 200+
Aramid LM 3600 60 1.45 40
Aramid HM 3100 120 1.45 80
Aramid UHM 3400 180 1.47 120
Glass - E glass 2400 69 2.5 27
Glass - S2 glass 3450 86 2.5 34
Glass - quartz 3700 69 2.2 31
Aluminum Alloy (7020) 400 69 2.7 26
Titanium 950 110 4.5 24
Mild Steel (55 Grade) 450 205 7.8 26
Stainless Steel (A5-80) 800 196 7.8 25
HS Steel (17/4 H900) 1241 197 7.8 25
Source: www.netcomposites.com
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Thermoplastic Composites
Importance of Fiber Length
Models predict that over
90% strength of
continuous fibercomposite is achieved
when fiber aspect ratio
approaches 2000
This correlates to glassfiber lengths of ~1.3
and carbon fiber Lengths
of ~0.6
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Composite Performance
versus Fiber Length for PP/Glass
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0.1 1 10 100Length (mm)
RelativeProperty
Level
Modulus
Strength
Impact
Processibility
Short Fiber ContinuousFillers Long Fiber
Source: OCF
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Impact and Fiber Length
Source: Ticona
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Key Factors
Fiber length
Fiber dispersion
Fiber impregnation
processing conditions and
technique
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The Long Fiber Advantage
Stress is transferred to the
fibers - the structural
members of the composite
Long fibers create askeletal structure within
the molded article that
resist distortion and
provide unmatched
strength, toughness, and
overall performance
Source: Ticona
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High-Performance Thermoplastic
Composites
Properties are fiber dominated
Oriented long or continuous fiber reinforcement
High volume fiber fraction (up to 65% by volume)Key benefits:
Reducing thermal limitations (e.g. creep) caused by the TP
matrix system
Reducing costs and weight and retaining toughness,
formability, weldability, short cycle times, recycling are
benefits of the thermoplastic matrix
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Continuous Fiber Advantage
In continuous oriented fibers the load is ultimately
fully transferred to the fiber
As a result tensile creep is limited in fiber direction
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History Of Low Cost
Thermoplastic Composites
Year1972 1980 1990 2000
GMT/AzdelLFT /LNP
Inj. Mold
LFT/Ticona
CompressionMolding
LFT concentrates
Twintex /
Vetrotex
Azdel SuperliteD-LFT
Compr. Mold.
D-LFT
Inj. Mold.
D-LFT
chopped fiber
Compr. Mold.
(CPI)
VW Golf A4 front end carrierFirst front end in GMT
VW Passat front end carrier
First front end in D-LFT
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House Of Production
Successful Part Production
MaterialSelection
Selectionofthe
ManufacturingPro
cess
Design
Internal/Extern
al
Knowledge
Economics
Part Requirements / Specification / VOC
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House Of Production - Often Seen
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Semi-Finished Materials
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Commercial Semi-Finished Materials
GMT (Glass Mat ReinforcedThermoplastics) Needled mat
Extrusion process
Slurry process (e.g. AzdelSuperLite)
Pultruded Products LFT (Long Fiber Reinforced
Thermoplastics)
CFT (Continuous FiberReinforced Thermoplastics)
Wire coated products
Commingled fibers
Powder coated materials
Film stacking
Self-reinforced materials
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GMT
Needling of the Mat
Source: Symalit (Quadrant Plastics Composites)
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GMT
The Consolidation Process
Source: Symalit (Quadrant Plastics Composites)
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Slurry Based ProcessThe AZDEL
SuperLite as an Example
Source: AZDEL
S i i C i
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Short Fiber, Long Fiber and Continuous
Fiber Composites
Typical short fiber
thermoplastic
material,
granules with fiberlength of approx. 2
to 4 mm,
resulting fiber length
in a part of approx.
0.4 mm
Long fiber
thermoplastic material,
pellets of and 1
fiber length, resultingfiber length in a part of
approx. 4-6 mm in
injection molding and
approx. 20 mm in
compression molding
Continuous
reinforced
thermoplastic
material, tape usedfor woven sheets
(thermoforming),
filament winding
or pultrusion
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70%i s Pr ocess Technol ogy
30%i s Pr oduct Composi t i on
Cooling
Haul-off/
Puller Pelletizer
Cleaning
Finishing
Packaging
Block
Glass
The Pultrusion Process
Courtesy of GEN
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Typical Pultruded Prepregs
Fiber: E-glass, S-glass, Carbon, Aramid, polymer fibers, metal
fibers
Matrix:
PE, PP, PA (6, 6/66, 12, ), PET, PBT, PC, PEI, PPS,SMA, blends,
Fiber content: 20% - 60% standard, some up to 84%
Product forms: Tape, pellets (0.5, 1), woven tapes more complex textile structures in development
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Typical Use of GMT and LFT Today
Processes
GMT compression molding
LFT-pellet approach
Direct LFT approach LFT mainly used in compression molding and
injection molding
Applications
Semi-structural and non-structural applications
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GlassTP
Commingling
Roving
Extruder
Source: Vetrotex
TwintexPrepreg
Temperature+ Pressure
Source: Vetrotex
E Glass
adapted sizing
Plastic filament
Additives :- coupling agent
- UV stabilizer
- natural or black
Source for all pictures: Vetrotex (OCV)
Twintex - Commingled Fiber Products
T i t C i l d Fib P d t
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Twintex - Commingled Fiber Products
Today OCV and Fiber Glass
Industries (license from OCV)
Fiber/matrix combinations:
E-glass/PP, E-glass/PET
Fiber content:
53 % and 70 % by weight
Product forms:
Roving, fabric (1:1, 4:1),
consolidated fabric, pellets
Specfic Tensile Properties of Polymer Matrix Composites
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 1 2 3 4 5 6
Metals
Continuous Uni-directional
Carbon Composites
LFT Glass
Composites
Continuous Uni-directional Glass
Composites
LFT Carbon
Composites
Plastics
Glass & Carbon
LFT & Continuous
Other Fibers
Varying Fiber Orientations
Twintex
Limitations:
Matrix material must be usable for a fiber spinning processlimitations in MFI/viscosity, additive type and additive content
Twintex
P d I t d P
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Powder Impregnated Prepregs
The Hexcel TowFlex-Technology
Source: Hexcel
Fiber Creel
Racks
Fluidized Bed
Powder Coating
Chamber
IR Oven PullerTake-up
System
Charged ResinPowder
To Weaving
To Tapes
To Pellets
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Hexcel TowFlex
Typical fibers:
Carbon, E-glass, S-
glass
Typical resins: PP, PA6, PPS, PEI,
PEEK
Typical product forms:
Flexible Towpreg
Woven fabric
Braided Sleeving
Unidirectional Tape
Specfic Tensile Properties of Polymer Matrix Composites
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 1 2 3 4 5 6
Specific Strength (x106
in.)
SpecificModulus(x108i
n.)
Metals
Continuous Uni-
directional Carbon
Composites
LFT Glass
Composites
Continuous Uni-directional
Glass Composites
LFT Carbon
Composites
Plastics
Glass & Carbon
LFT & Continuous
Other Fibers
Varying Fiber Orientations
Carbon Towflex
Glass Towflex
`
TowFlexGlass Carbon
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Film Stacking
Layers of fibers and thermoplastic film materials areplaced above each other and consolidated in a doublebelt press with a heating and cooling zone (similar tothe GMT process)
Glass, carbon, aramid fibers and combinations aretypically used
Most of thermoplastic resins available
Impregnation/wet out sometimes tricky Typically used as a semi-finshed material for
thermoforming
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Curv
Self-reinforced polypropylene Consists of hot compacted polypropylene fiber or tape
Surface of tape or fiber melts during compaction to form the matrixthat binds the directional elements together
Oriented morphology provides over six-fold increase in tensile
strength and nearly 5-fold increase in tensile modulus overisotropic polypropylene, with ~2% weight penalty
Nearly doubles tensile strength of 40% random mat short glasspolypropylene, with comparable modulus and 22% weightsavings
Elimination of glass reinforcement has several advantages: Increased recyclability
Reduced weight
Lower temperatures and pressures for thermoforming
High strain to failure, with good impact strength
Data from A New Self-Reinforced Polypropylene Composite Jones, Renita S. and Derek E. Riley
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Manufacturing Processes
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Manufacturing Processes for TP-Composites
Low volume manufacturing processes
Discontinuous processes
Thermoforming
Thermoplastic S-RIM, RTM and VARTM
Thermoplastic filament winding
Vacuum bag molding
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Manufacturing Processes for TP-Composites
High volume manufacturing processes Discontinuous processes Injection molding with
LFT-pellets and concentrates (high performance resin/fiber combinations)
Inline compounding (high performance resin/fiber combinations)
Back molding / local reinforcement
Compression molding LFT-pellets and concentrates (high performance resin/fiber combinations) Inline compounding (high performance resin/fiber combinations)
Back molding / local reinforcement
Stamp forming Preheated preforms
Matched metal tools
Potential to manufacture very thin sections (0.5 to 1 mm) Drapable material required
Continuous processes Pultrusion
LFT-extrusion
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Current Composite Materials and Processes
Process Type of Application
Injection Molding
Compression
Molding
Thermoforming
Hand Lay Up /
Vacuum Bag /
Autoclave
Low-Structural
Components
Semi-Structural
Components
Structural Components
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Low Volume Manufacturing Processes
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Thermoforming
Heat in Oven Thermoforming
Operation
Finished
Product
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Thermoforming
Weight performance: Good weight/performance ratio for fabric reinforced sheets due tocontinuous fibers
Reduced weight/performance ratio for extruded sheets depending onthe resulting fiber length
Design flexibility: Limited, especially for complex geometries
Simulation tools available
Processing: Stabilization against oxidation necessary
Fiber misalignments with continuous fibers possible depending on
geometry, material, tooling and process conditions Recycling:
High rate of production scrap (fixation)
No direct recycling
Use in other processes like plastication or regranulation
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VARTM / RTM / S-RIM
Process VARTM RTM S-RIM
Typical Injection
Pressure
1 bar 5 bar 50 bar
Tooling Single sided tool Double sided tool Double sided steel
tool
Injection Unit Mixing vessel Pressure vessel,
most cases no
mixing heat
Separate tanks for
each component,
mixing head
Typical
Achievable Fiber
Volume Content
40% 40 % 55%
Reactive Thermoplastic
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Reactive Thermoplastic
VARTM/RTM/S-RIM
Similar the thermoset process
Reaction of at least two components creates a
thermoplastic resin that can be melted, pre-
shaped, welded,
Low viscosity is required
Possible materials: Nylon, TPU, C-PBT
(Cyclics)
Process Technology Of The Anionic
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Process Technology Of The Anionic
Polymerization Of Caprolactam
Explanations
1. Storage vessel for caprolactam
2. Reactor for caprolactam with
activator
3. Reactor for caprolactam with
catalyst
4. Mixing head
5. Mold, heated
6. Flexible tube
7. Mixing head, valve
Flowchart
Source: Brueggemann Chemical U.S., Inc.
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TP S-RIM, RTM, VARTM
Weight/performance: Excellent
Design flexibility: Limited to preforming capability, flow length and flow
behavior of the resin
Processing: Reaction can be sensitive to moisture and fiber sizing
Recycling:
Production scrap due to preforming step depending onpreforming method
No direct recycling; can be used in other processes
Materials Used For Liquid Molding
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Materials Used For Liquid Molding
Processes
Materials used for liquid molding processes
Cyclics
Reactive Nylon
Fulcrum
Requirement for these materials
Viscosity less than 3000 mPa.s (cP) (better lessthan 1000 mPa.s (cP))
Viscosity influences achievable fiber content
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Cyclics
Cyclic form of PBT, PET, PC and others
Only PBT commercial available
Based on a ring shaped cyclical form
One or two part systems Solid at room temperaturelow viscosity resin at
elevated temperature (approx. 150 cP)
Polymerize into the Polymer using a catalyst
Isothermal process
Typical process temperature: 180200 oC
C t P l id 6 P l id 6
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Cast Polyamide 6 vs. Polyamide 6
There are differences between Cast Polyamide 6 and Polyamide 6 chips.
Production:
Use of simple inexpensive molds possible High part weights with various thickness
Efficient for low quantities
Material:
Improved mechanical properties Better wear resistance Better crystalline structure, higher crystallinity
Source: Brueggemann Chemical U.S., Inc.
Basic Principles Of Nylon Casting
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Basic Principles Of Nylon Casting
Raw Materials
-Caprolactam: AP-Quality (Anionic Polymerization) water content
< 200ppm
Catalyst: Sodium-Caprolactam used in concentration of
app. 1.2- 3.0%
Activator: Caprolactam blocked isocyanate or similar used
in concentration of app. 1.0-2.5%
Cast Polyamide 6 vs. Injection Molded
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Cast Polyamide 6 vs. Injection Molded
Polyamide 6
Examples of mechanical properties
TENSILE STRENGTH
0
1020
30
40
50
60
70
Nylon 6 Cast Nylon 6
N/mm
MODULUS OF ELASTICITY
0
1000
2000
3000
4000
Nylon 6 Cast Nylon 6
N/mm
Source: Brueggemann Chemical U.S., Inc.
F l
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Fulcrum
ISOPLAST matrix (Dow proprietary engineeringthermoplastic polyurethane)
Thermoplastic viscosity issues addressed by ability toreverse polymerization in the melt stage, reducingviscosity to ensure good impregnation
Repolymerizes upon cooling, retaining traditional
thermoplastic composite advantages High impact resistance
Recycling
High elongation to failure (~2.5%, versus ~1-1.5% forthermosets)
Zero-emissions processing
Fulcrum is the combination of ISOPLAST andpultrusion, with specific hardware design
Provides 10-fold line speed improvement overtypical thermoset pultrusion lines
Allows thermoforming, welding, and overmolding of
finished pieces
Thermoformed Fulcrum Components
Figures from Fulcrum Thermoplastic Technology; Making High-Performance Composite via Thermoplastic Pultrusion Dow Plastics, January 2000
Problems Connected With Reactive
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Problems Connected With Reactive
Thermoplastic Molding
Reaction can be stopped or made incomplete
by
MoistureChemicals in fiber sizing
Most of the thermoplastic compatible sizings are not
developed for such type of processes
Availability of compatible sizings in form of fabric isvery limited
Oxygen
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TP Filament Winding
Typically done with pre-impregnated fibers
Weight/performance: Excellent
Design flexibility: Limited to symmetric parts that can be wound on a mandrel
Processing: Higher oxidative stabilization required
Recycling: Low rate of production scrap
No direct recycling
Scrap can be used in other processes
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Vacuum Bag
Weight/performance Excellent due to continuous fiber reinforcement
Design flexibility Limited to drapability and to the possibility of manually lay up
Processing Higher void content due to low pressure consolidation
Using autoclave to reduce void content
Often fiber dealignments
Recycling High rate of production scrap possible depending on the size of the
material sheets and the part geometry No direct recycling
Scrap can be reused in other processes
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High Volume Manufacturing Processes
Extrusion /Compression
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Extrusion /Compression
Molding
Shot exiting extruder / plasticator
Shot placed on tool
Molded part
Tool in press
M f t i P U i LFT P ll t
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Manufacturing Processes Using LFT-Pellets
Injection Molding
Injection and injection compression molding
Low pressure molding
Compression Molding
Plasticator
Continuous extrusion Flying knife and belt plunger
Source: C.A. Lawton
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Problematic General Purpose Screw
Source: Krauss-Maffei
Compression Molding
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Compression Molding
of Thermoplastic Composites
GMT LFT ILCmanufacturing of mats pultrusion of the
semi-finished product
(manufacturing of PP-film)
extrusion of matrix and
consolidation using adouble belt press
(cutting of the GMT-sheets)
heating in GMT-oven plastication in-line compounding
material handling material handling material handling
compression molding compression molding compression molding
Semi-finished
Material
Pa
rtproduction
R lti Fib L th i P t
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Resulting Fiber Length in a Part
I li C di
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Inline-Compounding
Processes using chopped fibers only CPI Binani
JCI (slurry process (Fibrolen, plastication process)
Processes using rovings (most of them capable for choppedfibers)
Compression Molding Berstorff
Coperion
Dieffenbacher
Lawton LMG
PlastiComp
Injection Molding Husky
Krauss Maffei
PlastiComp
P T h l i F LFT
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Process Technologies For LFT
Compression (GMT) little fiber damage
small fiber orientation
high impact strength
Compression (LFT-D, LFT-G/P)
reduced cost for intermediate
product
thin wall thickness possible
variability of fiber content
Injection Molding
reliable and stable process
technology
good surface quality
variability of fiber content
no finishing work necessary
GMT
LFT-D
LFT-G/P
LFT-D
IMC
LFT-G/P
Compression Injection Molding
Fiberlengthi
nt
he
part
Source: Krauss Maffei
ILC Injection Molding
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ILC Injection Molding
Pictures: KraussMaffei
Proprietary
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Proprietary
Compounding System
***All materials are gravimetrically fed for precise content***
Overhead View
Th Di ff b h S t
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The Dieffenbacher-System
Picture: Rieter
Th Di ff b h S t
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The Dieffenbacher System
Source: Dieffenbacher
The Coperion S stem
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The Coperion System
1 Polymer pellets 5 Twin-screw compounder ZSK 8 Separating unit
2 Gravimetric feeder 6 Devolatilizing 9 Robot
3 Rovings 7 Cutting unit 10 Press
4 Motor and gearbox
Source: Coperion
The Berstorff System
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y
Source: Berstorff
The Lawton System
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The Lawton System
Conveyers
Flat Sheet Die
Roving System
Four-Component Gravimetric
Feeder
Twin Screw Pre-
Plasticator
Control Panel
Reciprocating Screw
Plasticator
Single
Component
Gravimetric
Controlled
Vibrational
Feeder
Vibratory Track Vacuum
Feeder from
Octabin
Source: Lawton
PlastiCompPushtrusion
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p
Injection Molding
Source: PlastiComp
PlastiComp
Pushtrusion
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Compression Molding
Source: PlastiComp
Material For D-LFT Processes
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Material For D-LFT Processes
Polymer PP (most cases)
PA
Other technical thermoplastic resins
Fiber reinforcements
Roving Chopped Fibers
68mm, 12 mm, long chopped fibers
Additives Process and heat stabilization
Coupling UV stabilization
Color
Flame Retardants
Polymer
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Polymer
PP most common
All major PP supplier
Some PP supplier have their own additive package as a
concentrate
Typical MFI 3080, sometimes higher
Homo- and Copolymers used
Nylons and others
Viscosity must allow wet out and impregnation Similar or lower viscosity used as for PP
Heat and process stabilization is much more an issue
Glass Fiber Roving
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Glass Fiber Roving
Glass Melt
Bushing
Applicator
Gathering Shoe
Fiber
Winder Dryer
Finishing
Packaging
Water Spray
Chopped Strand
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Chopped Strand
Glass Melt Bushing
Applicator
Gathering Shoe
Fiber
Winder
Dryer / Separator
Water Spray
Chopper[ ]Densification
Sizing The Interface
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SizingThe Interface
Sizing = coating of the fiber
Often applied as a water based solution during
the fiber forming process
Can be a complex mixture of chemicals
including coupling agents, film forming
polymers, lubricants, anti-foaming aids,
dispersants, fillers, stabilizers, and others
Function of a Sizing
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Function of a Sizing
Protection of fibers
during manufacture
during shipment
during processing by customers Easy to meter and feed
no fuzz
Easy to disperse
Improve wet out
Chemical coupling of fiber and resin
Sizing and Properties
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Sizing and Properties
Some functions of sizings are contradictory
easy to disperse and easy to feed
Mechanical performance of the final composite part
is controlled by the coupling agent other sizing chemicals are neutral or reduce mechanical
performance
Fiber dispersion in a final part is important for
consistency of mechanical performance
surface quality
Chemical Coupling
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Chemical Coupling
Polypropylene and fiber glass can bechemically coupled by using
Aminosilane functionality in the sizing
Maleic anhydride grafted polypropylene in theresin
The matrix polypropylene is crystallizingaround the MaH-PP that is coupled to the fiber
Interface is a combination of chemical andmechanical coupling
Influence of Additives
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Influence of Additives
Pigmentation
Carbon black changes flow and wet out characteristics
Pigments with sharp edges damage fiber
All pigmentation can influence crystallinity Impact Flame retardants
Higher processing temperatures in the LFT processes
(compared to short fiber TP) can start the reaction of the
flame retardant already during the process High influence on Dynatup impact in most cases: 5% flame
retardant can reduce impact by 20% and more.
Comparison of LFT-Processes
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Comparison of LFT-Processes
Process Average Fiber Length Warpage / FiberOrientation
Throughput
Injection Molding of
Short Fiber Compounds
0.4 mm Lowmedium High
Injection Molding of
LFT-Pellets (12.7 mm)
4 mm High High
Injection Molding of
LFT (ILC)
4 - 10 mm High High
Compression Molding of
LFT-pellets (25 mm)
20 mm Medium Medium;
concentrates: low
In-Line Compounding
Compression Molding
15 to 35 mm Medium High
Increasing Properties on LFT Parts
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Increasing Properties on LFT Parts
Sizing developments / Optimization Co-molding with unidirectional or multidirectional
inserts Compression and injection molding
LFT-extrusion with continuous reinforcement (includingbraiding)
Co-Thermoforming
Increase/design orientation of fibersby flow design
By reactive resin approach
Changing fiber/resin combination
Effects on Material and
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Equipment
Most of the engineering thermoplastic resins are moresensitive to degradation due to heat, air and moistureas polypropylene
Processing equipment and compounding additives
has to compensate for this sensitivity
If material is exposed to air, the stabilization has to beadjusted for the exposure time
All compression molding lines need higher stabilization
levels compared to injection molding lines
If material is deposited continuously on a belt, an additionalamount of stabilization is recommended
Effects on Material and
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Equipment
Moisture sensitive resins:
Resins should be dried before use
A hopper dryer is recommended for all types of D-LFTequipment when running moisture sensitive materials
A high volume vacuum degassing system can be
used
The Co-Molding Concept:
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Carbon fiber
ribs (depth
exaggerated)
Insert
Integration of Frame for a Bus Seat
Source: FTA-AL-26-7001.1
SEAT TOOL WITH INSERTS
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SEAT TOOL WITH INSERTS
Source: FTA-AL-26-7001.1
MANUFACTURING CONCEPT
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MANUFACTURING CONCEPT
Compression molding with LFT-pellets
Compression back molding of carbon-fiber
reinforced inserts with long glass fiber reinforced
pellets
Insert will be preheated (if necessary) in an oven and
placed in the tool immediately before the compression
molding step
Geometry of plasticated material as a result of
flow simulation
PROCESSING OF INSERTS
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PROCESSING OF INSERTS
PP/fiber tapes back molded with LFT
Insert at tool side LFT will not melt the insert
enough to get good bonding
Insert at top of the LFT charge good bonding
Insert should be preheated directly before
processing
PROCESSING OF INSERTS
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PROCESSING OF INSERTS
Fibers of the inserted tape,
cut against fiber direction
PP rich area
LFT, random fiberorientation
Source: FTA-AL-26-7001.1
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Pultrusion
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Pultrusion
Weight/performance Good to excellent due to continuous reinforcement
Design flexibility
Low design flexibility
Limited to constant cross sections, but can be shaped (pull/press)
Processing
Only limited experience available
Depends on stabilization of the material as well as used material form
Recycling
Low rate of production scrap expected
No direct recycling
Can be used in other processes
LFT-Extrusion
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t us o
Weight/performance Medium weight performance
Depends on retaining fiber length
Design flexibility Low design flexibility
Limited to constant cross sections Can be post shaped or pull formed
Processing Not a lot of experience
A stable process is expected using the right die design
Recycling Low rate of production scrap
Can be reused in the same process
Simulation - Comparison of Filling Behavior
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and Flow Simulation
Result of flow simulation Short shot shows filling behavior
Source: FTA-AL-26-7001.1
Joining
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g
With the increase of mechanical properties,
joining techniques play a more important role
and are part of system design
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Economics
Cost Challenge
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Costsin
$/lb
Automotive Structures$1 - $3/lb
Innovative Materials andProcesses$5 - $20/lb
Typical Aerospace Structure$50 - $100/lb
and more
Materials:Glass Fiber / Polypropylene, SMC/BMC
Processes:Compression Molding, Injection Molding
Materials:Thermoplastic Woven Sheets, Glass,Carbon and Kevlar Fiber, Engineering
PolymersProcesses:
Co-Compression Molding, Co-Injection Molding, Thermoforming
Materials:Carbon Fiber / Epoxy, Carbon
Fiber / BMI, Carbon Fiber /PEEK
Processes:Hand Lay Up
Apply Materials andProcessing Techniques
being Developed forAutomotive Applications to
Aerospace Applications
Economics
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Process Cycle Time Tooling Costs Scrap Rate Overall Economics
Thermoforming Medium Low High Good for low volume productionwith no or limited thickness variation
TP S-RIM, RTM,
VARTM
Medium to long, up to several
minutes
VARTM: low,
single sided tool
RTM: low to
medium
S-RIM: Medium
Depends on
preforming
technique;
often high for
complex
shaped parts
Good for low volume production
TP Filament Winding Medium to long, depending onnumber of tapes and heating system
Low to medium Low Good for symmetrical parts in low tomedium volume production
Vacuum Bag/
Hand Lay-up
Long; manual preparation can be
hours for a part
Low, single sided
tool
Medium to
high
Good for prototyping. Not
recommended for production scale.
Injection Molding
-LFT
-ILC
Short cycle times; typically 5080
sec.
High; steel tools
with ejector pins
and slides
Very low Excellent for high volume
production
Compression Molding-GMT
-LFT
-ILC
Short cycle times; typically 3560sec.
High; steel toolswith ejector pins
and slides
Lowmediumdepends on cut
outs. Scrap can
be reused
Excellent for high volumeproduction of large components
Pultrusion Continuous process; not enough
experience on throughput
Medium Low Limited experience available
Extrusion Continuous process; throughput
mainly limited by cooling capacityof calibration die
Medium to high Low Expected to be cost
effective for profiles
Cost Factors for High Volume Component
P d ti
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Production
Direct costs:
Material costs
Labor costs
Cycle Time
Energy and water
Quality costs
Indirect costs: Equipment costs / depreciation
Floor Space
Maintenance
Overhead Costs
Other costs:
Development costs Tooling costs
Material Costs
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All material costs are based on PP and 30% glass fiber
GMT 125 %
LFT-pellets 100 %
LFT-concentrates 85 %
Direct-LFT (raw materials) 60 %
Short fiber granules 75 %
Material Costs Including Recycling
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All material costs are based on PP and 30% glass fiber and
20% recycled scrap, costs for shredder included.
100% = LFT-pellets without recycling.
GMT 125 %
LFT-pellets 85 %
LFT-concentrates 70 %
Direct-LFT (raw materials) 48 %
Short fiber granules 62 %
Labor Costs
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Injection Molding:1 worker / shift can run multiple lines
Compression Molding:Labor costs directly correlated with the degree of
automation
No automation: average 2 to 3 workers / shift(depending on the component)
High automation: 1 worker / shift
Equipment Costs
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q p
Corrected for same throughput and a typical part size and
including post operations, if necessary
GMT 100 %
LFT-pellets 100 % LFT-concentrates 103 %
Direct-LFT 115 %
Injection molding 60 %
D-LFT injection molding 80 %
Quality Costs
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y
Related to receiving inspection test
GMT and LFT-pellets:
testing done by material supplier
only limited testing is necessaryLFT-concentrates and ILC:
different material supplier
no material supplier will take over responsibility
more test effort
material development responsibility
Quality Costs
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Related to production problems and stability
material development problems:
flow problems
long term properties mechanical properties
non-stable process
bad part design
flow problems
warpage
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Manufacturing Decisions
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Decisions on Pellet-LFT D-LFT and type ofequipment depends on multiple factors, such as
Volume and part size
Experience
Location and labor costs
Company and cost structure
Development capabilities
Has to be calculated for every case/company
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Applications
Applications
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Type of applications Metal Replacement (integration and design possibilities)
Replacement of unfilled, filled and short-fiber reinforced TPs
Corrosion resistance
Shielding (metal fiber or carbon fiber reinforced)
Typical areas Automotive
Leisure and sporting goods
Infrastructural and housing
Electrical
Office Furniture
Others
Most of the applications today are in high volume segments such as automotive
Applications For High-Performance
Thermoplastic Composites
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Thermoplastic Composites
Aerospace and defense: Radomes, wing and fuselage sections, anti-ballistics
Infrastructure and construction
Window profiles, rebar, beams, structures, composite bolts
Consumer / recreational Orthotics, safety shoes, sporting goods, helmets, personal injuryprotection, speaker cones, enclosures, bed suspension slats
Auto and truck
Bumper beams, skid plates, load floor, seat structures
Transportation Railcar structure, body structure and closures
Energy production and storage
Oil and gas structural tube, wind turbines
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Outlook
The Future of ThermoplasticComposites
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Composites
Will go to more structural applications usingdifferent technical thermoplastics in combination withglass, carbon and synthetic fibers.
Will replace metal applications and reduce weight.
Improved processing methods will be developed andapplied.
Future of LFT
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LFT will expand into more structural applications and in applications thatrequire higher surface quality
This will be realized by using engineering thermoplastic resins additional toPP
The major volume of LFT production will still be based on PP for the next
few years Roving and chopped fibers will each have their applications due todifferent part requirements
Combinations of LFT with in-mold decoration or painting will expand
Other fiber combinations (e.g. natural fiber) will get a bigger share on themarket
Fabric reinforcement in combination with compression molding of LFT isproviding new applications for thermoplastic composites.
The process of local reinforcement creates a lot of new opportunities bycombination of a cost effective process and high performance.
Acknowledgements
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Federal Transit Administration
SRI - Southern Research Institute
UABUniversity of Alabama at Birmingham
Allan Murray, Ecoplexus Inc.
Ed McDade, BrueggemannChemical US Inc.
All materials and equipment companiesreferred in the presentation
Contact Information
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Klaus F. Gleich
Johns Manville Technical Center
10100 W. Ute AveLittleton, CO 80127
Phone: 303-978-2286
Email: [email protected]
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Questions ?
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