Forged Molding Compound - Speautomotive

Forged Molding Compound High Performance Chopped Carbon Fiber CompositesSteven WusterbarthMitsubishi Chemical AmericaSteven Wusterbarth@m-chem.comKoichi AkiyamaGemini Composites LLC A subsidiary ofMitsubishi Chemical Carbon Fiber and CompositesKoichi.Akiyama@mccfc.com

Agenda Traditional Carbon Fiber SMC Forged Molding Compound (FMC ) Technology FMC Material FMC Process FMC Design ConclusionMitsubishi Chemical Carbon Fiber Applications

Carbon Fiber Sheet Molding Compound (CF SMC) CF SMC is a chopped fiber moldingcompound– Relatively large tow size of carbon fiber iscommonly used– Small tow carbon fiber is too expensive forindustrial applications– Vinyl ester resin is typical matrix resin systemSMC Production CF SMC is usually molded bytraditional compression molding– Cure time is relatively short; suitable forhigh cycle molding– SMC is normally squeezed to flow andfill complex geometryCompression Molding

Example of Carbon Fiber SMC applications2017 ToyotaPrius2018 LexusLC500Prime Rearhatch innerpanelDoor innerpanel2018 KTM2018 LexusLC500Skid plateDecklidinner panel

Suitable application for CF SMC and limitation Suitable for secondary structural or aesthetical applications– Most of those applications are designed for stiffness– Complex geometry can be molded– Snap cure material enables high cycle molding for high volume applications Limitations for use in primary structural applications– Material can’t keep isotropic fiber orientation and mechanical propertiesduring traditional compression molding process– Mechanical properties of common CF SMC are insufficient– Large variation of mechanical properties– Sophisticated FEM analysis and design technique were unavailable

Forged Molding Compound (FMC ) technology Forged Molding Compound (FMC ) isthe integrated technology of choppedcarbon fiber compositesMaterial FMC technology consists of threefactors.– Advanced material– Optimized molding process– Dedicated design The ideal combination of the three factorsof FMC enables metal replacement withcarbon fiber composites, achievingsignificant weight reduction of structuralapplications.ProcessDesign

Advanced Chopped Carbon Fiber Composites FMC technology was developed for primary structural applications– FMC material is high performance sheet molding compound made withadvanced chopped carbon fiber, which provides higher strength and specificmodulus than light-weight metal– Snap cure material enable high cycle molding for high volume applications– Properties of advanced materials can be fully utilized in the molded part byoptimizing the molding process– Dedicated FMC design replaces metal design– FEM analysis technique specialized for FMC is availableMaterialProcessDesign

MaterialSmaller CF tow provides ideal structure Homogeneous structure provide excellent mechanical propertiesand dimensional stability– More fiber layers exist in the same thickness of 3K material than larger tow– Less resin-rich area is observed in 3K material15K 53%3K 53%

Fiber bundle size has strong influence on mechanical properties– The smaller and thinner bundles gives the higher and more homogeneous mechanical properties– Property variation significantly lowers the value used for parts designTensile StrengthTensile sle Strength (MPa)MaterialEffect of Carbon Fiber Tow Size on Mechanical Property2502001501005003KCF 53%Avg15KCF 53%3-sigma404035353030252520201515101050503KCF 53%3KCF 53%AverageAvg15KCF 53%15KCF 53%3-sigma3-sigma

MaterialSmall Tow CF SMC Provides Excellent Properties; However Small tow CF SMC is good for certain applications, but there arelimitations for use in industrial applications– The SMC cost is high due to the high expense of smaller tow carbon fiber– Limited moldability of complex geometriesSmall TowCF SMC Complex GeometriesMaterialCostLarge TowCF SMC

MaterialFMC Material Advanced Chopped Carbon Fiber Composites FMC material is high performance sheet molding compound made withadvanced chopped carbon fiber to provide an economic solution withexcellent properties– The chopped fiber has tow size distribution providing excellent mechanicalperformance and good moldability– Split tow-based advanced chopped fiber provides an affordable solution FMC material contains many thin layers of carbon fiber tow– Homogeneous structure without the resin-rich portion also provides excellentproperties

MaterialFMC Material Product Line A variety of FMC products are available– Fiber contents and length can be chosen depending on application requirements– Both vinyl ester and epoxy matrix resin systems are available– Flame retardant and high Tg grades are under development and will be available soonRegular Carbon Fiber15K / Vinyl Ester3K / Vinyl EsterAdvanced Carbon FiberVinyl EsterEpoxy

FMC made with advanced carbon fiber provides higher strength than 3K CF SMC withthe same fiber contentMechanical Properties of 60% fiber content vinyl ester materialFlexural Strength & Modulus400403003020020100100015KTensile Strength3KFMC Tensile ModulusFlexural Strength (MPa)Tensile Strength & ModulusTensile Strength (MPa)MaterialFMC Material Excellent Mechanical al Strength3KFMC Flexural Modulus

FMC can be made with any fiber content from 40% to 65%– The resin system and fiber content can be specified depending on desired mechanicalproperties or other application requirementsFlexural Strength & ModulusTensile Strength & Modulus3004025020030150100204045Vinyl EsterEpoxy5055Fiber Content (%)Tensile StrengthTensile Strength60Tensile ModulusTensile Modulus65Tensile Mduus (GPa)350505504045035030250150204045Vinyl EsterEpoxy5055Fiber Content (%)Tensile StrengthTensile Strength6065Tensile ModulusTensile ModulusFlexural Mduus (GPa)65050Flexural Strength (MPa)400Tensile Strength (MPa)MaterialFMC Material Carbon Fiber Content

FMC made with advanced carbon fiber flows better than 3K CF SMC– FMC flows well even though tow size is small to provide higher property than 3K CF– Low flow molding is essential for FMC , however good moldability is still quite important to moldcomplex geometry.Spiral FlowSpiral Flow of Vinyl Ester Material60053% 3K53% FMCMCC Standard Test MethodWidth of channel: 5cm, Thickness of Channel: 2mmPlunger pressure: 10Mpa, Mold Temp: 140 CSpiral Flow (mm)MaterialFMC Moldability Spiral flow500400300200100015KCF Content 53%3KFMC CF Content 60%

FMC carries carbon fiber better into complex geometry such as ribs.– Advanced CF keeps isotropic fiber orientation better than regular CF during molding– Advanced CF retains 85% and 66% of nominal tensile strength in top and rib specimens respectivelyTensile Strength Retention of Top & Rib SpecimensDeep Rib MoldingTop SpecimenRib SpecimenDeep Rib Molding ConditionMold Coverage: 95% charge only on top, no insert in ribPart Thickness: Top 2.0 mm, Rib root 3.0mm, Rib top 2.0mmRib Height: 43mm, Rib Draft angle: 1 degreeMolding pressure: 10Mpa, Mold Temp: 140 CStrength Retention (%)MaterialFMC Moldability Deep Rib Part Molding10080604020015KTop Specimen3KRib SpecimenFMC

ProcessFMC Process Low Flow Molding Minimizing material flow during molding process––––Minimal material flow prevents sacrificing mechanical propertiesOptimizing the change pattern by shape and weight distribution is the keyUtilizing a preformed charge pattern is recommendedLow flow molding-friendly part design makes a large impact on propertiesHigh Flow MoldingExcessive FlowFMC processHighFlowMoldingMinimal Flow

ProcessMaterial Flow During Compression MoldingFMC Low Flow MoldingLow flow specimen shows more uniform strain distribution and parallel tow/fiber breakageTraditional High Flow MoldingHigh flow specimen show high strain concentration area, swirling ad fiber bunching, single fracture point

ProcessFiber orientation after material flow during molding Material flow orientates carbon fiber and makes a swirl of fiber– Fiber aligns along to direction of material flow– At the flow front of material, a swirl of fiber occurs and creates defectsLow Flow Molding 95% coverage95%High Flow Molding 50% coverage50%300x300mm flat panelMaterial:CF SMC PTO130N127Vinyl ester matrix resin1” 53% 3K CFPanel Thickness:3.2–3.4mmMolding Temperature: 140 CMolding Pressure:10 MPaCure time:3 minutesCharge pattern:95% coverage50% coverage

Material flow significantly changes mechanical properties Fiber orientation creates anisotropic and inhomogeneous propertiesMechanical Properties After Material Flow During MoldingTensile Strength (MPa)ProcessMechanical Properties After Material Flow During Molding4005040300302002010010000º90º95% CoverageTensile Strength0º90º50% CoverageTensile Modulus300x300mm flat panelMaterial:CF SMC PTO130N127Vinyl ester matrix resin1” 53% 3K CFPanel Thickness:3.2–3.4mmMolding Temperature: 140 CMolding Pressure:10 MPaCure time:3 minutesCharge pattern:95% coverage50% coverage

DesignFMC DesignDesign philosophy of FMC technology is completely different fromthat for either metal or continuous carbon fiber composites. FMC parts design is dedicated to chopped fiber material. Parts should be designed as material flow can be minimized duringcompression molding. So the parts can keep isotropic fiberorientation and mechanical property. FEM analysis and simulation optimized for FMC material should beused. Holes, thickness change, molded-in inserts can be used, which isdifficult in the case of traditional continuous carbon fiber composites.

DesignFMC Design Example Suspension Prototype FMC design was developed forsuspension prototype part.FMC Design–Size; 362(L)x63(W)x70(H)mm–Thickness; 3–13 mm–Prototype parts were manufactured and itsproperty was evaluatedMetal Design

FMC design can make composite partstronger than metal part– Example: Automotive suspension part Compression property– Rev II: FMC design with the right material andprocess achieved higher load than ultimate failureof aluminum part. More than 40% weight reductionCompression Failure LoadDesignFMC Design ImprovementsAluminumPart UltimateAluminumPart YieldRev 0Rev IRev 0 Rev 0: Typical material substitutionRev I: Material and Process are good, butdesign is metal design.Rev IIRev IRev IIDesignAluminum partdesignAluminum partDesignFMC DesignMaterial15K CF SMCFMC FMC Molding ProcessTraditional HighFlowFMC Low FlowFMC Low FlowWeight Reduction fromAluminum Part47%47%41%

DesignFMC Cost Competitiveness to Aluminum Cost of compression molding is normally lower than metal forging FMC material is moreexpensive than aluminum.– However mass of FMC partis 60% of aluminum part.– 40% of impact can bededucted. Molding cycle of FMC is short. FMC can mold complexgeometry, so most ofmachining can be eliminated. Total process cost is lowerthan metal forgingParts cost comparison(Anonymous primary structural part. Cost is index, not dollar 0%0%FMC PartAluminum Part60100Part Weight Ratio

In Conclusion FMC technology has been developed as the lightweight solution for primarystructural applications with high production volumes. The advanced chopped carbon fiber is the key technology of FMC material,which provides high mechanical performance and excellent moldability at anaffordable cost. FMC technology consists of not only advanced material, but also optimizedmolding process and dedicated design. The combination of those threefactors enables utilization of chopped carbon fiber compositeto primary structural applications that require highMaterialmechanical performance. FMC technology can be utilized in a variety of structuralapplications such as large body structure, suspension,DesignProcesspower train, crash box, EV battery enclosure and more.