机械类文献翻译基于注塑模具钢研磨和抛光工序的自动化表面处理

英文原文AutomatedsurfacefinishingofplasticinjectionmoldsteelwithsphericalgrindingandballburnishingprocessesAbstractThisstudyinvestigatesthepossibilitiesofautomatedsphericalgrindingandballburnishingsurfacefinishingprocessesinafreeformsurfaceplasticinjectionmoldsteelPDS5onaCNCmachiningcenter.Thedesignandmanufactureofagrindingtoolholderhasbeenaccomplishedinthisstudy.TheoptimalsurfacegrindingparametersweredeterminedusingTaguchi’sorthogonalarraymethodforplasticinjectionmoldingsteelPDS5onamachiningcenter.TheoptimalsurfacegrindingparametersfortheplasticinjectionmoldsteelPDS5werethecombinationofanabrasivematerialofPAAl2O3,agrindingspeedof18000rpm,agrindingdepthof20μm,andafeedof50mm/min.ThesurfaceroughnessRaofthespecimencanbeimprovedfromabout1.60μmto0.35μmbyusingtheoptimalparametersforsurfacegrinding.SurfaceroughnessRacanbefurtherimprovedfromabout0.343μmto0.06μmbyusingtheballburnishingprocesswiththeoptimalburnishingparameters.Applyingtheoptimalsurfacegrindingandburnishingparameterssequentiallytoafine-milledfreeformsurfacemoldinsert,thesurfaceroughnessRaoffreeformsurfaceregiononthetestedpartcanbeimprovedfromabout2.15μmto0.07μm.KeywordsAutomatedsurfacefinishing·Ballburnishingprocess·Grindingprocess·Surfaceroughness·Taguchi’smethod1IntroductionPlasticsareimportantengineeringmaterialsduetotheirspecificcharacteristics,suchascorrosionresistance,resistancetochemicals,lowdensity,andeaseofmanufacture,andhaveincreasinglyreplacedmetalliccomponentsinindustrialapplications.Injectionmoldingisoneoftheimportantformingprocessesforplasticproducts.Thesurfacefinishqualityoftheplasticinjectionmoldisanessentialrequirementduetoitsdirecteffectsontheappearanceoftheplasticproduct.Finishingprocessessuchasgrinding,polishingandlappingarecommonlyusedtoimprovethesurfacefinish.Themountedgrindingtools(wheels)havebeenwidelyusedinconventionalmoldanddiefinishingindustries.Thegeometricmodelofmountedgrindingtoolsforautomatedsurfacefinishingprocesseswasintroducedin.Afinishingprocessmodeofsphericalgrindingtoolsforautomatedsurfacefinishingsystemswasdevelopedin.Grindingspeed,depthofcut,feedrate,andwheelpropertiessuchasabrasivematerialandabrasivegrainsize,arethedominantparametersforthesphericalgrindingprocess,asshowninFig.1.Theoptimalsphericalgrindingparametersfortheinjectionmoldsteelhavenotyetbeeninvestigatedbasedintheliterature.Fig.1.SchematicdiagramofthesphericalgrindingprocessInrecentyears,someresearchhasbeencarriedoutindeterminingtheoptimalparametersoftheballburnishingprocess(Fig.2).Forinstance,ithasbeenfoundthatplasticdeformationontheworkpiecesurfacecanbereducedbyusingatungstencarbideballoraroller,thusimprovingthesurfaceroughness,surfacehardness,andfatigueresistance.Theburnishingprocessisaccomplishedbymachiningcentersandlathes.Themainburnishingparametershavingsignificanteffectsonthesurfaceroughnessareballorrollermaterial,burnishingforce,feedrate,burnishingspeed,lubrication,andnumberofburnishingpasses,amongothers.TheoptimalsurfaceburnishingparametersfortheplasticinjectionmoldsteelPDS5wereacombinationofgreaselubricant,thetungstencarbideball,aburnishingspeedof200mm/min,aburnishingforceof300N,andafeedof40μm.Thedepthofpenetrationoftheburnishedsurfaceusingtheoptimalballburnishingparameterswasabout2.5microns.Theimprovementofthesurfaceroughnessthroughburnishingprocessgenerallyrangedbetween40%and90%.Fig.2.Schematicdiagramoftheball-burnishingprocessTheaimofthisstudywastodevelopsphericalgrindingandballburnishingsurfacefinishprocessesofafreeformsurfaceplasticinjectionmoldonamachiningcenter.TheflowchartofautomatedsurfacefinishusingsphericalgrindingandballburnishingprocessesisshowninFig.3.Webeganbydesigningandmanufacturingthesphericalgrindingtoolanditsalignmentdeviceforuseonamachiningcenter.TheoptimalsurfacesphericalgrindingparametersweredeterminedbyutilizingaTaguchi’sorthogonalarraymethod.FourfactorsandthreecorrespondinglevelswerethenchosenfortheTaguchi’sL18matrixexperiment.Theoptimalmountedsphericalgrindingparametersforsurfacegrindingwerethenappliedtothesurfacefinishofafreeformsurfacecarrier.Toimprovethesurfaceroughness,thegroundsurfacewasfurtherburnished,usingtheoptimalballburnishingparameters.Fig.3.Flowchartofautomatedsurfacefinishusingsphericalgrindingandballburnishingprocesses2DesignofthesphericalgrindingtoolanditsalignmentdeviceTocarryoutthepossiblesphericalgrindingprocessofafreeformsurface,thecenteroftheballgrindershouldcoincidewiththez-axisofthemachiningcenter.Themountedsphericalgrindingtoolanditsadjustmentdevicewasdesigned,asshowninFig.4.Theelectricgrinderwasmountedinatoolholderwithtwoadjustablepivotscrews.Thecenterofthegrinderballwaswellalignedwiththehelpoftheconicgrooveofthealignmentcomponents.Havingalignedthegrinderball,twoadjustablepivotscrewsweretightened;afterwhich,thealignmentcomponentscouldberemoved.Thedeviationbetweenthecentercoordinatesoftheballgrinderandthatoftheshankwasabout5μm,whichwasmeasuredbyaCNCcoordinatemeasuringmachine.Theforceinducedbythevibrationofthemachinebedisabsorbedbyahelicalspring.Themanufacturedsphericalgrindingtoolandball-burnishingtoolweremounted,asshowninFig.5.Thespindlewaslockedforboththesphericalgrindingprocessandtheballburnishingprocessbyaspindle-lockingmechanism.Fig.4.SchematicillustrationofthesphericalgrindingtoolanditsadjustmentdeviceFig.5.(a)Photoofthesphericalgrindingtool(b)Photooftheballburnishingtool3Planningofthematrixexperiment3.1ConfigurationofTaguchi’sorthogonalarrayTheeffectsofseveralparameterscanbedeterminedefficientlybyconductingmatrixexperimentsusingTaguchi’sorthogonalarray.Tomatchtheaforementionedsphericalgrindingparameters,theabrasivematerialofthegrinderball(withthediameterof10mm),thefeedrate,thedepthofgrinding,andtherevolutionoftheelectricgrinderwereselectedasthefourexperimentalfactors(parameters)anddesignatedasfactorAtoD(seeTable1)inthisresearch.Threelevels(settings)foreachfactorwereconfiguredtocovertherangeofinterest,andwereidentifiedbythedigits1,2,and3.Threetypesofabrasivematerials,namelysiliconcarbide(SiC),whitealuminumoxide(Al2O3,WA),andpinkaluminumoxide(Al2O3,PA),wereselectedandstudied.Threenumericalvaluesofeachfactorweredeterminedbasedonthepre-studyresults.TheL18orthogonalarraywasselectedtoconductthematrixexperimentforfour3-levelfactorsofthesphericalgrindingprocess.Table1.Theexperimentalfactorsandtheirlevels3.2DefinitionofthedataanalysisEngineeringdesignproblemscanbedividedintosmaller-thebettertypes,nominal-the-besttypes,larger-the-bettertypes,signed-targettypes,amongothers[8].Thesignal-to-noise(S/N)ratioisusedastheobjectivefunctionforoptimizingaproductorprocessdesign.Thesurfaceroughnessvalueofthegroundsurfaceviaanadequatecombinationofgrindingparametersshouldbesmallerthanthatoftheoriginalsurface.Consequently,thesphericalgrindingprocessisanexampleofasmaller-the-bettertypeproblem.TheS/Nratio,η,isdefinedbythefollowingequation:η=−10log10(meansquarequalitycharacteristic)=−10log10where:yi:observationsofthequalitycharacteristicunderdifferentnoiseconditionsn:numberofexperimentAftertheS/NratiofromtheexperimentaldataofeachL18orthogonalarrayiscalculated,themaineffectofeachfactorwasdeterminedbyusingananalysisofvariance(ANOVA)techniqueandanF-ratiotest.Theoptimizationstrategyofthesmaller-thebetterproblemistomaximizeη,asdefinedbyEq.1.Levelsthatmaximizeηwillbeselectedforthefactorsthathaveasignificanteffectonη.Theoptimalconditionsforsphericalgrindingcanthenbedetermined.4ExperimentalworkandresultsThematerialusedinthisstudywasPDS5toolsteel(equivalenttoAISIP20),whichiscommonlyusedforthemoldsoflargeplasticinjectionproductsinthefieldofautomobilecomponentsanddomesticappliances.ThehardnessofthismaterialisaboutHRC33(HS46).Onespecificadvantageofthismaterialisthataftermachining,themoldcanbedirectlyusedforfurtherfinishingprocesseswithoutheattreatmentduetoitsspecialpre-treatment.Thespecimensweredesignedandmanufacturedsothattheycouldbemountedonadynamometertomeasurethereactionforce.ThePDS5specimenwasroughlymachinedandthenmountedonthedynamometertocarryoutthefinemillingonathree-axismachiningcentermadebyYang-IronCompany(typeMV-3A),equippedwithaFUNUCCompanyNC-controller(type0M).Thepre-machinedsurfaceroughnesswasmeasured,usingHommelwerkeT4000equipment,tobeabout1.6μm.Figure6showstheexperimentalset-upofthesphericalgrindingprocess.AMP10touch-triggerprobemadebytheRenishawCompanywasalsointegratedwiththemachiningcentertoolmagazinetomeasureanddeterminethecoordinatedoriginofthespecimentobeground.TheNCcodesneededfortheball-burnishingpathweregeneratedbyPowerMILLCAMsoftware.ThesecodescanbetransmittedtotheCNCcontrollerofthemachiningcenterviaRS232serialinterface.Fig.6.Experimentalset-uptodeterminetheoptimalsphericalgrindingparametersTable2summarizesthemeasuredgroundsurfaceroughnessalueRaandthecalculatedS/NratioofeachL18orthogonalarraysingEq.1,afterhavingexecutedthe18matrixexperiments.TheaverageS/NratioforeachlevelofthefouractorsisshowngraphicallyinFig.7.Table2.GroundsurfaceroughnessofPDS5specimenExp.Innerarray(controlfactors)Measuredsurfaceroughnessvalue(Ra)ResponsenoABCDS/N(η(dB))Mean111112122231333421235223162312731328321393321101122111233121311132113142221152332163131173212183323Fig.7.PlotsofcontrolfactoreffectsThegoalinthesphericalgrindingprocessistominimizethesurfaceroughnessvalueofthegroundspecimenbydeterminingtheoptimallevelofeachfactor.Since−logisamonotonedecreasingfunction,weshouldmaximizetheS/Nratio.Consequently,wecandeterminetheoptimallevelforeachfactorasbeingthelevelthathasthehighestvalueofη.Therefore,basedonthematrixexperiment,theoptimalabrasivematerialwaspinkaluminumoxide;theoptimalfeedwas50mm/min;theoptimaldepthofgrindingwas20μm;andtheoptimalrevolutionwas18000rpm,asshowninTable3.TheoptimalparametersforsurfacesphericalgrindingobtainedfromtheTaguchi’smatrixexperimentswereappliedtothesurfacefinishofthefreeformsurfacemoldinserttoevaluatethesurfaceroughnessimprovement.Aperfumebottlewasselectedasthetestedcarrier.TheCNCmachiningofthemoldinsertforthetestedobjectwassimulatedwithPowerMILLCAMsoftware.Afterfinemilling,themoldinsertwasfurthergroundwiththeoptimalsphericalgrindingparametersobtainedfromtheTaguchi’smatrixexperiment.Shortlyafterwards,thegroundsurfacewasburnishedwiththeoptimalballburnishingparameterstofurtherimprovethesurfaceroughnessofthetestedobject(seeFig.8).ThesurfaceroughnessofthemoldinsertwasmeasuredwithHommelwerkeT4000equipment.TheaveragesurfaceroughnessvalueRaonafine-milledsurfaceofthemoldinsertwas2.15μmonaverage;thatonthegroundsurfacewas0.45μmonaverage;andthatonburnishedsurfacewas0.07μmonaverage.Thesurfaceroughnessimprovementofthetestedobjectongroundsurfacewasabout(2.15−0.45)/2.15=79.1%,andthatontheburnishedsurfacewasabout(2.15−0.07)/2.15=96.7%.Fig.8.Fine-milled,groundandburnishedmoldinsertofaperfumebottle5ConclusionInthiswork,theoptimalparametersofautomatedsphericalgrindingandball-burnishingsurfacefinishingprocessesinafreeformsurfaceplasticinjectionmoldweredevelopedsuccessfullyonamachiningcenter.Themountedsphericalgrindingtool(anditsalignmentcomponents)wasdesignedandmanufactured.TheoptimalsphericalgrindingparametersforsurfacegrindingweredeterminedbyconductingaTaguchiL18matrixexperiments.TheoptimalsphericalgrindingparametersfortheplasticinjectionmoldsteelPDS5werethecombinationoftheabrasivematerialofpinkaluminumoxide(Al2O3,PA),afeedof50mm/min,adepthofgrinding20μm,andarevolutionof18000rpm.ThesurfaceroughnessRaofthespecimencanbeimprovedfromabout1.6μmto0.35μmbyusingtheoptimalsphericalgrindingconditionsforsurfacegrinding.Byapplyingtheoptimalsurfacegrindingandburnishingparameterstothesurfacefinishofthefreeformsurfacemoldinsert,thesurfaceroughnessimprovementsweremeasuredtobegroundsurfacewasabout79.1%intermsofgroundsurfaces,andabout96.7%intermsofburnishedsurfaces.中文译文基于注塑模具钢研磨和抛光工序的自动化表面处理摘要这篇文章研究了注塑模具钢自动研磨与球面抛光加工工序的可能性，它可以在数控加工中心完成注塑模具钢PDS5的塑性曲面。这项研究已经完成了磨削刀架的设计与制造。最佳表面研磨参数是在钢铁PDS5的加工中心测定的。对于PDS5注塑模具钢的最佳球面研磨参数是以下一系列的组合：研磨材料的磨料为粉红氧化铝，进给量50毫米/分钟，磨削深度20微米，磨削转速为18000RPM。表面粗糙度Ra值可由大约微米改善至微米，通过用优化的参数进行表面研磨。如果用球抛光工艺和参数优化抛光，还可以进一步改善表面粗糙度Ra值，一般从微米至微米左右。而在模具内部曲面的测试部分，用最佳参数的表面研磨、抛光，曲面表面粗糙度就可以提高约微米至微米。关键词:自动化表面处理抛光磨削过程表面粗糙度田口方法一、引言步距研磨高度球磨研磨进给速度工作台由于塑胶工程材料的重要特点,比如耐化学腐蚀性、低密度、易于制造,并且已经日渐取代了金属部件在工业中广泛应用。在注塑成型领域，其对于塑料制品是一个重要工艺。设计的本质要求是注塑模具的表面质量步距研磨高度球磨研磨进给速度工作台图1球面研磨过程示意图研磨工具(轮子)的安装的磨削工具（车轮）已被广泛地用在常规的模具和模具精加工产业。安装的几何模型的整理工序引入英寸甲球面磨削工具自动化表面精加工处理模式的状态下，完成系统开发英寸磨削速度，切削深度，进给速率，如研磨材料和车轮属性自动化表面的磨削工具。和磨料颗粒的大小，是用于球形研磨过程的主要参数，如在图所示。1。的最佳的球形研磨参数用于注射模具钢中尚未调查是根据在文献中。在最近几年中，已经进行了一些研究，在确定球抛光过程（图2）的最优参数。比如，已发现，可以减少使用的钨硬质合金球或辊在工件表面上的塑性变形，从而改善表面粗糙度，表面硬度和耐疲劳性。抛光过程是通过加工中心和车床。主要的抛光参数，具有显着的表面粗糙度的影响的滚珠或滚子材料，抛光力，进给速率，抛光速度快，润滑和抛光通行证的数量，等等。最佳的表面的塑料注射模具钢PDS5挤光参数的组合的润滑脂，碳化钨球的抛光速度为200毫米/分钟，抛光力，300N，和一个饲料为40μm。使用的最佳球抛光参数的磨光表面的渗透深度为约2.5微米。通过抛光过程中的改进的表面粗糙度一般介于40％和90％之间。图2球面抛光过程概略图本文研究的目的是开发球面磨削球抛光表面处理工艺的自由曲面，塑料注塑模具加工中心。自动化表面精加工的流程图中，使用球面磨削和球抛光过程示于图3中。我们开始设计和制造的球面磨削加工中心上使用的工具，其定位装置。最佳的表面球面磨削参数进行了测定，利用田口正交阵列的方法。四个因素，三个相应的级别，然后选择为田口L18矩阵实验。的最佳安装球面磨削参数，然后将其应用于自由曲面载体的表面光洁度的表面研磨。为了改善表面粗糙度，地面进一步打磨，使用的最佳球挤光参数。PDS试样的设计与制造PDS试样的设计与制造选择最佳矩阵实验因子确定最佳参数实施实验分析并确定最佳因子进行表面抛光应用最佳参数加工曲面测量试样的表面粗糙度球研磨和抛光装置的设计与制造图3自动球面研磨与抛光工序的流程图二、球研磨的设计和对准装置要进行可能的球形研磨过程中的自由曲面，球研磨机的中心应与z-轴的加工中心重合。的安装的球形研磨工具和其调整装置的设计，如在图所示。4。电动研磨机中，安装在工具保持架有两个可调的枢轴螺钉。以及研磨机球的中心对准的圆锥槽的取向组分的帮助。对准的粉碎机球，两个可调节的支点螺丝拧紧后，对齐组件可以被删除。中心之间的偏差的坐标球研磨机的柄部的时间是约5微米，这是由一个数控三坐标测量机测量。由振动引起的力的机床吸收由一个螺旋弹簧。所制造的球形研磨工具和球磨光工具被安装，如图所示5。主轴被锁定的球面研磨过程和球抛光由主轴锁定机构的方法。模柄模柄弹簧工具可调支撑紧固螺钉磨球自动研磨磨球组件图4球面研磨工具及其调整装置图5a球面研磨工具的图片.b.球抛光工具的图片三、矩阵实验的规划田口正交表几个参数的影响，可以有效地进行矩阵实验田口直交。要与上述球形研磨参数相匹配，研磨机的球（直径为10毫米），进给速度，磨削深度，和革命的电动研磨机的研磨材料被选定为四个实验因素（参数）并指定为因子A到D（见表1），在本研究中。每个因子的三个层次（设置）被配置为覆盖感兴趣的范围内，并确定了数字1，2，和3。三种类型的研磨材料，即，白色氧化铝（Al2O3，WA），碳化硅（SiC）和粉红色的氧化铝（Al2O3，宾夕法尼亚州），选择和研究。每个因子的三个数值的预研究结果的基础上确定的。L18直交被选中的4个3级因素的球面磨削过程中进行矩阵实验。表1实验因素和水平因素水平123A.碳化硅白色氧化铝粉红氧化铝B.50100200C.研磨深度（µm）205080D.120001800024000数据分析的界定工程设计问题,可以分为较小而好的类型,象征性最好类型,大而好类型，目标取向类型等。信噪比(S/N)的比值，常作为目标函数来优化产品或者工艺设计。被加工面的表面粗糙度值经过适当地组合磨削参数，应小于原来的未加工表面。因此,球面研磨过程属于工程问题中的小而好类型。这里的信噪比（S/N）,η,按下列公式定义:η=−10log平方等于质量特性=−10log