Engineering_Plastics_Design_Guide_-_Material_Selec

EnginEEringPlasticsMaterialSelectionaDeSignguiDeintroDuction2Becauseofimprovedqualityandcostcompetitiveness,plasticmaterialsaredisplacingtraditionalmaterialsinamyriadofdiverseanddemandingindustries.Today,engineeringplasticscanbefoundinvirtuallyeveryaspectofourlives.Fromfoodcontainerstoautomobiles,appliances,toys,officeequipment,andlife-savingmedicaldevices,plasticsaffecteachandeveryoneofus.Productdesignersandconsumersalikeacknowledgethattoday’sadvancedplastics,intandemwithproperdesign,addtoproductvalueandversatility.Thegrowingnumberofthermo-plastics—withtheircombinationsofphysicalandmechanicalproperties—makesthepropermaterialselectiondifficult.Aresinisjudgedbyanynumberofcriteria—strength,tough-ness,aesthetics,etc.—dependinguponapart’sfinaluse.Anyparticularplastic’sperformanceacrossthesecriteriacanvarywidely.Thismanualisdesignedtohelpyou—thedesignengineer,productengineer,processengineer,andotherswhoworkwithplasticmaterials—selectmaterialsforyourspecificapplication.Itbeginswithabasicoverviewofthenatureofplastics,thenexplainsthespecifictestsusedtocompareandevaluateengineeringplastics.Wehopethisinformationhelpsyoudevelopparameterstoconsiderwhenselectingagroupofplasticsforfurtherinvestigation.Manyrulesofthumbappearinthetext.Naturally,theremaybesomeexceptionstotheserulesofthumbortimeswhenoneconflictswithanother.Ifthishappens,talkwithyourmoldmaker/designerandLANXESSCorporationpersonnelforappropriateaction.Specificresindataandtypicalpropertyinformationhavenotbeenincludedinthismanualexceptasexamplesforgeneralinformation.Allvaluesthatappearinthismanualareapproximateandarenotpartoftheproductspecifications.Donotusethisdataforproductspecification.Formorespecificinformationonaparticularresin,pleasereadtheappropriateLANXESSProductInformationBulletin(PIB)asapreliminarystepformaterialselec-tion.Ultimately,materialselectionmustbebaseduponyourproto-typetestingunderactual,end-useconditions.Thisbrochuredoesnotcoverpartdesign.Whiledesignandmaterialselectionareinterrelated,wehavechosentodiscusspartandmolddesigninaseparatemanual,EngineeringPlastics:PartandMoldDesignGuide.Throughoutthismanual,relevanttestsfromtheAmericanSocietyforTestingandMeasurement(ASTM),theInter-nationalStandardsOrganization(ISO),Underwriters’Laboratories(UL),GermanStandardsInstitute(DIN),andtheInternationalElectro-TechnicalCommission(IEC)aregiven,wherepossible.EffortsweremadetoincludethepertinenttestsspecifiedinISO10350—theemerginginterna-tionalstandardforpolymerpropertiesandtestprocedures.Whileprovidingagoodoverviewofthetopicsyoushouldconsiderwhenselectingaplastic,thismanualdoesnotprovidealltheinformationyou’llneedtomakeafinalresinchoice.Finalmaterialselectionmustbebaseduponprototypetestinginformationandfinalparttestinginactual,in-usesettingspriortocommercialization.Publisheddatashouldbeusedonlytoscreenpotentialcandidatematerials.Page2of70:Thisdocumentcontainsimportantinformationandmustbereadinitsentirety.tableofcontentSChapter1unDerStanDingengineeringPlaSticS6Plastics:OriginsandDefinitions7ThermoplasticsandThermosets8CrystallineandAmorphousPolymers9Blends10CopolymersandTerpolymers10MolecularWeight10FillersandReinforcements11Shrinkage12Additives12CombustionModifiers12ReleaseAgentsChapter2MecHanicalbeHaViorofPlaSticS13Viscoelasticity14Creep15StressRelaxation15Recovery16LoadingRate16FactorsAffectingMechanicalProperties17Processing17ThermoplasticRegrind18WeldLines19ResidualStress20Orientation21WaterAbsorption22ChemicalExposure22WeatheringChapter3MecHanicalProPertieS23Short-TermMechanicalProperties23TensileProperties25TensileModulus25TensileStressatYield25ElongationatYield26TensileStressatBreak26ElongationatBreak26UltimateStrength27Poisson’sRatio27FlexuralProperties27FlexuralModulus27UltimateFlexuralStress28CompressiveProperties28CompressiveStrength29ShearStrength29ImpactProperties32HardnessProperties34MiscellaneousMechanicalProperties34CoefficientofFriction34AbrasionandScratchResistance35Long-TermMechanicalProperties36CreepProperties37StressRelaxation38FatigueProperties3tableofcontentS4Chapter4tHerMalProPertieS40DeflectionTemperatureUnderLoad(DTUL)41CoefficientofLinearThermalExpansion(CLTE)41ThermalConductivity42SpecificHeat42RelativeTemperatureIndex(RTI)42VicatSofteningTemperature43TorsionalPendulumChapter5electricalProPertieS44VolumeResistivity44SurfaceResistivity45DielectricStrength46DielectricConstant46DissipationFactor46ArcResistance47ComparativeTrackingIndex(CTI)48Hot-WireIgnition(HWI)48High-CurrentArcIgnition(HAI)48High-VoltageArc-TrackingRate(HVTR)Chapter6enVironMentalProPertieS49WaterAbsorption49HydrolyticDegradation50ChemicalResistance51Weatherability52GasPermeabilityChapter7otHerProPertieS53Density53SpecificGravity53SpecificVolume54HazeandLuminousTransmittance54RefractiveIndex54OxygenIndex54FlammabilityClassChapter8ProPertieSuSeDinProceSSing57GeneralProcessingParameters57MoldShrinkage57Viscosity57SolutionViscosity58ViscosityVersusShearRateCurves59Thermoplastics59MeltFlowRate59SpiralFlowChapter9MaterialSelection:tHingStoconSiDer61CostConsiderations62En