注塑成型简介.ppt

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1、注射成型基本原理簡介注塑成型是一种注射兼模塑的成型的方法,又稱注射成型.是塑料成型加工最普通也是最早的成型方法.注塑過程包括預塑,計量,注射,充模,泠卻定型等過程,得到一定幾何形狀和精度的塑件制品.注塑工藝參數的選擇和調整及原料,模具,設備對制品質量將產生直接影響.前言目錄塑膠特性簡介成型基本原理成型常見不良及分析材料塑料(高分子)熱固性熱塑性工程通用無定型結晶性無定型結晶性PCABSMPPOPEIPPSPETPOMPAPMMAPSPVCPEPPInjectionMoldingPlastic塑料類型塑膠分子結構InjectionMoldingP

2、lasticRaiseTemperatureofPolymerAddingheatincreasesspacebetweenmolecularchainsbutcrystallinestructurepreventsflow.ModelofCrystallinePolymersRigidSolidSoftSolidFlowsEasilyTGTMInjectionMoldingProcess固態難於流動較易流動InjectionMoldingProcessModelofAmorphousPolymersAddingHeatIncreasesSpa

3、ce外热提供空间BetweenMolecularChains在分子链之间RaiseTemperatureofPolymerTGLocked固态EntanglementsStiffFlow难于流动EasierFlow较易流动InjectionMoldingVariablesMeltTemperature熔融温度35302520151050.030.060.090.120.150.180.210.240WallThicknessinInches壁厚(In)MeltFlow(in.)LEXAN?101550degF.101@600deg.FIncre

4、asedMeltTemperatureyieldsincreasedFlow.提高熔融温度导致增加流动However,TooHighaMeltTemperatureMayCauseDegradation.但,过高熔融温度造成降解InjectionMoldingMaterialThermoplasticsandDegradation热塑性塑料和降解Degradation降解TemperatureTime时间InjectionMoldingBarrelUnitTheReciprocatingScrew(Filling)ThroatHeatingCo

5、ilsNozzleHopperBarrelForce,TorqueFromInjectionUnit料筒组件回转式螺杆喷嘴加热料斗加料口料筒来自注塑单元的力和力矩計量區熔融區加料區Screw螺杆InjectionMoldingBarrelUnitTheReciprocatingScrewScrewRotationFeedsandShearsMaterialIntoaMelt.MeltCollectsIntoFrontofBarrel,ForcingScrewBackShotRotationandBackPressure出量通过螺杆回转，熔体聚集

6、于料筒前部，反作用力使螺杆后退。回转力矩和背压熔化混合InjectionMoldingEquipmentBarrelUnitTheReciprocatingScrewShotInjectionPressure注射压力流動射出在一定壓力,速度下熔體從噴嘴流道澆口型腔的充填成型過程InjectionFlow熔融流動InjectionMoldingProcessInjectionMoldingVariablesInjectionSpeed100010010100100010000LEXAN?141@644degFLEXAN?141@608degFLE

7、XAN?141@572degFApparentViscosity(Pa/s)ShearRate(1/s)InjectionSpeedaffectstheviscosityofthemoltenmaterial.注射速度表观粘度剪切速率注射速度影响熔体粘度InjectionMoldingVariablesInjectionPressureProfileHydraulicPressureTimeFillTimeScrewRunTimeBackPressurePeakInjectionPressurePressureAppliedbyInjectio

8、nRamtoForcethePlasticFromtheBarreltotheMold.注射压力曲线注射压力峰值液压压力填充时间壓縮保壓保压Packi