機(jī)械設(shè)計(jì)及自動(dòng)化外文翻譯

本科畢業(yè)設(shè)計(jì)外文文獻(xiàn)及譯文文獻(xiàn)、資料題目：TheImpactAnalysisofStampingProcessFactorsBasedonDynaform文獻(xiàn)、資料來源：AdvancedMaterialsResearch文獻(xiàn)、資料發(fā)表日期：2013院〔部〕：機(jī)電工程學(xué)院專業(yè)：機(jī)械工程及自動(dòng)化班級(jí)：機(jī)械成型方向姓名：學(xué)號(hào)：指導(dǎo)教師：翻譯日期：外文文獻(xiàn):TheImpactAnalysisofStampingProcessFactorsBasedonDynaformAbstractCombiningwithpracticalneedsinproduction,itcarriedoutthenumericalsimulationanalysisofautomobilebeamstampingformingprocessbasedonDynaforminthispaper.Accordingtoqualityevaluationindexofformingparts,itanalyzedtheeffectofvariationofblankholderforce,thestampingspeed,thecoefficientoffrictionanddrawbeadonstampingquality.Itforecastthequalityproblemshappenedinformingprocess,whichprovidesthetheoreticalbasisfordesignofstampingprocessandmold.Keywords:stampingforming,numericalsimulation,processfactors,impactanalysis,DynaformIntroductionDuetohighproductionefficiency,lowprocessingcostsandstabilityofproductdimensionalaccuracy,sheetmetalstampingiswidelyusedinthefieldofautomobilemanufacturing[1-3]biningwithpracticalneedsinproduction,itcarriedoutthenumericalsimulationanalysisofautomobilebeamstampingformingprocessbasedonDynaforminthispaper,andanalyzedtheeffectofmanufacturingprocessfactorsonstampingquality,andachievedtheaimofoptimizingstampingprocessparametersandreducingmoldtrialnumber.EstablishmentoffiniteelementmodelAccordingtotechnicalrequirementsofautomobilebeamputtedforwardbyautomobilemanufacturerandstampingprocesses,thethree-dimensionalmodelwasbulitwithcraftsupplementwhichmeetsthenumericalsimulationrequirementsusingUG.Withimportingthethree-dimensionalmodelintoDynaform,themodelwasmeshbyquadrilateralusingtheadaptivegridtechnology.Thencheckandrepairthefiniteelementmodel.Thefiniteelementmodelofpunchanddiewasestablishedbyusingthecopycommand.Thestampingdirectionwasadjustedaccordingtotheactualcircumstances[4-5].Theblanksheet,blankholder,thedieclearanceandthepositioningwascompleted.ThefiniteelementmodelofstampingnumericalsimulationisshowedasFig.1EffectanalysisofprocessfactorsonstampingInfluenceofBlankHolderForceonforming.BHFinthesheetmetalstampingprocesscangenerallybeestimatedwiththefollowingformula:FBHF=Aq〔1〕Inequation(1),FBHFisblankholderforce(N);Aisthecontactareaofblankholderandblank(mm2);qistheblankholderforceperunitarea(MPa);InDynaform,theStaticfrictioncoefficientis0.125,thepunchingspeedis5000mm/s,theclearancebetweenpunchanddieis1.1t(tisthethicknessofsheet),andthedownmoldisfixedwithoutmoving[6-7].ItcarriedoutnumericalsimulationanalysisrespectivelywhenBHFaretakenasfourseries:490kN,540kN,590kN,630kN.TheForminglimitdiagraminnumericalsimulationisshowedinFig.2whiletheblankholderforceis590kN.ItcanbeseenfromFig.2,thepartdoesnotcrackedafterstamping,butwrinklingphenomenonisoccurredinedge.Itisindicatedthatthematerialflowisnotsufficientinthispositionwhichcausespartialthickening,that’swhytheprocessimprovementisneeded.Themaximumandminimumthicknessesofthepartarepresentedinthewastezone,whichhasnoeffectonthepartqualityfinally.Itfocusontheeffectiveareaofpartafterstamping,themaximumthinningrate,maximumthickeningrateandotherdateineffectiveareunderfourdifferentBHFaremanagedinTable1ItcanbeseenfromTable1,themaximumthinningrateisgraduallyincreasingandthemaximumthickeningrateshowsadecreasingtrendwhiletheBHFisincreasing.Thesetwoparametersaretheevaluationindexofsheetqualityafterforming,buttheycannotindicatetheequalitydegreeofsheetthicknessafterforming.Therefore,theuniformitydegreeofsheetthicknessafterformingischaracterizedbytheaveragethicknessanddeviationinthispaper.Theaveragethicknessisthemeanvalueofallthenodes’thicknessinthenumericalsimulation.Theaveragedeviationreferstothemeanvalueofabsolutedeviationbetweeneachnodesandtheaveragethickness,andthemathematicalexpressionoftheaveragedeviationis,whichisusedtoreflectthedispersiondegreeofeachnodethickness,i.e.theuniformitydegreeofsheetthickness.ItcanbeseenfromFig.3,astheblankholderforceincreasing,theaveragethicknessofpartisgraduallyreducing,whiletheaveragedeviationisincreasingstepbystep.ItisindicatedinthesepartthatthedispersiondegreeofeachnodesthicknessisincreasingalongwithBHFincreasing,andtheuniformityofthispartafterformingbecomesworse.Thus,underthecircumstanceofmeetingtherequirementofthinningandthickening,wecanchoosetheprocessprogramwithsmallerBHFinordertoimprovetheuniformityofpartafterformingintheactualproduction.Influenceofstampingspeedonforming.Fourprogramsofnumericalsimulationanalysisinwhichstampingspeedisrespectively4000mm/s,4500mm/s,5000mm/s,5500mm/swereconductedtoresearchtheimpactofstampingspeedonpartforming,whentheBHFis590kN.SomeanalysisdatawithfourprogramsofnumericalsimulationarecollatedinTable2.AsitcanbeseenfromTable2,withstampingspeedincreasing,themaximumthinningrateshowsanincreasingtrendandthereisapeakofmaximumthickeninginthisinterval.Withstampingspeedincreasing,theaveragethicknessofpartgraduallybecomesthickerafterstamping.Intheintervaloflowstampingspeed,thevalueofaveragedeviationislargeandwhenthestampingspeedislarge,thevalueisdecreased.Thatillustratesintheconditionofhighstampingspeed,theuniformityofpartafterstampingcouldbebetter.Thereforeintheactualproductionunderthecircumstanceofmeetingtherequirementofthinningandthickening,wecanchoosetheprocessprogramwithhigherstampingspeedinordertoimprovetheuniformityofpartafterformingaccordingtotheactualsituationofstampingequipment.Influenceoffrictioncoefficientonforming.Fourprogramsofnumericalsimulationanalysisinwhichcoefficientoffrictionisrespectively0.1,0.125,0.15,0.175werecarriedoutinthispaperwhenthestampingspeedis5000mm/sandtheBHFis590kN.Themaximumthinningrate,maximumthickeningrateandotherdateintheeffectiveareaaremanagedinTable3.ItcanbeseenfromTable3,ascoefficientoffrictionincreasing,themaximumthinningrateshowsadecreasingtrend,whilethemaximumthickeningratehasavalleyvaluesinthisintervalwithlittlevaluechange.Alongwithfrictioncoefficientincreasing,theaveragethicknessofpartdecreasesgraduallyandtheaveragedeviationincreasesstepbystep,andtheuniformityofpartafterformingbecomeworse.Thereforeintheactualproductionunderthecircumstanceofmeetingtherequirementofthinningandthickening,wecanchoosetheprocessprogramwithsmallercoefficientoffrictioninordertoimprovetheuniformityofthepartafterforming.Influenceofdrawbeadonforming.Forthispart,thetwodrawbeadsarerespectivelyarrangedontheupperandlowersideofthedie.ThelayoutofdrawbeadisshowninFig.4.InDynaform,thecontacttypeselectFPRMING_ONE_WAY_S_S.BHFis590kN,Staticfrictioncoefficientis0.125,thestampingspeedis5000mm/s,theclearancebetweenpunchanddieis1.1t,thedownmoldisfixedwithoutmoving.UndertheaboveconditiontheforminglimitdiagramwithdrawbeadandwithoutdrawbeadareshowninFig.4.ItcanbeobviouslyseenfromFig.5thatthesecurityarea(showningreen)oftheprogramwithdrawbeadismorethanitofprogramwithoutdrawbeadwhileotherparametersarethesame.Itindicatesthattheprogramwithdrawbeadhasthebetterconditionofmaterialutilizationandthewrinklingineffectiveregionhasbeenrelieved.Therefore,itcanimprovetheutilizationofthematerialduringformingwithdrawbead.Afteranalysisandcomparisonofprocessparameterswithdifferentvalues,combinedwithactualsituation,thefinalprocessparametersisasfollowing:theBHFis590kN,thestampingspeedis5000mm/sandthecoefficientofstaticfrictionis0.125,itselectsthedrawbeadlayoutshowninFig.4,finallytheforminglimitdiagramofnumericalsimulationisshowninFig.5(left).Theconsistencyisgoodcomparedwiththeactualproductionsituation.Conclusions(1)Thethinningrate,thickeningrate,stressandthestraindistributionafterstampingaretheimportantindicatorswhichcharacterizetheformingquality.Intheeffectivearea,themaximumvalueoftheseindicatorsshouldbefocusedon.Theuniformitydegreeofsheetafterstampingcanbecharacterizedbytheaveragethicknessandtheaveragedeviationthroughdataprocessing.(2)Takinganautomobile’sbeamformingasanexample,theimpactofBHF,stampingspeed,coefficientoffrictionanddrawbeadonformingqualityofstampingwasresearchedandthechangingtrendoftheimpactwasanalyzedinthispaper.Finallytheprocessparametersweredeterminedcombinedwithactualproductionsituation.Theresultofnumericalsimulationhasagreatagreementwithactualsituationofproduction.(3)Theimpactofmulti-factorsonthestampingqualitycanbestudiedwithanalysisofstampingsimulation.Itcantakeplacetherepeatedtryoutinactualproductiontoachievethepredictionandscientificityofstampingprocessplan,enhancetheaccurateandreliabilityofmolddesignanddecreasethecycleofmoldmanufacturinganddebugging,whichhascertainsignificancefortheactualproduction.References[1]HuangYao,ZhuQing,WangLeigang,“SimulationonMulti-stepsStampingforShockAbsorberLidBasedonDYNAFORM”,JournalofHotWorkingTechnology,vol.40,no.15,pp.73-75,2011.[2]HeberCastroSilva,SérgioFernandoLajarin,PauloVictorP,“MarcondesAnalysisofNumericallySimulatedTrueStrainonHighStampabilitySheets”,JournalofJanuary-March,vol.32,no.1,pp.21-27,2010.[3]Dae-CheolKo,Seung-HoonCha,Sang-KonLee,Chan-JooLee,Byung-MinKim,“Applicationofafeasibleformabilitydiagramfortheeffectivedesigninstampingprocessesofautomotivepanels”,JournalofMaterialsandDesign,vol.31,pp.1262–1275,2010.[4]WanMin,LiDongsheng,QiaoLihong,Thecomputeranalysistechnologyofsheetmetalforming,BeiHangUniversityPress,China,2008.[5]BaoXiangjun,JiangHongfan,HeDannong,LiCongxin,“NumericalSimulationoftheInfluenceofMaterialParametersonAutobodyPanelStampingFormability”,JournalofMaterialsforMechanicalEngineering,vol.25,no.7,pp.15-17,2001.[6]XieHui,“Analysisofcriticalstressandpredictionofsheet'swrinklinginsheetmetalforming”,JournalofComputationalMechanics,vol.20,no.1,pp.96-100,2003.[7]Bor-TsuenLin,Chun-ChihKuo,IntJAdv,“ApplicationofanintegratedCAD/CAE/CAMsystemforstampingdiesforautomobiles”,JournalofManufTechnol,vol.35,pp.1000–1013,2008.中文翻譯：基于Dynaform沖壓工藝的影響因素分析摘要結(jié)合生產(chǎn)實(shí)際需要，在本文中，基于DYNAFORM進(jìn)行了汽車大梁沖壓成形過程數(shù)值模擬分析。根據(jù)零件的成形質(zhì)量評(píng)價(jià)指標(biāo)，分析了壓邊力變化的影響，沖壓速度，摩擦和拉延筋的沖壓質(zhì)量系數(shù)。它預(yù)測成形過程中發(fā)生的質(zhì)量問題，為沖壓工藝及模具設(shè)計(jì)提供了理論依據(jù)。關(guān)鍵詞：沖壓成形，數(shù)值模擬，工藝因素，影響分析，模擬引言由于生產(chǎn)效率高，加工本錢低、產(chǎn)品尺寸精度穩(wěn)定，沖壓件廣泛應(yīng)用于汽車制造領(lǐng)域。結(jié)合生產(chǎn)實(shí)際需要，在本文中基于DYNAFORM進(jìn)行了汽車大梁沖壓成形過程的數(shù)值模擬分析，并分析了制造工藝因素對(duì)沖壓件質(zhì)量的影響，并實(shí)現(xiàn)了優(yōu)化工藝參數(shù)，減少試模次數(shù)的目的。有限元模型的建立根據(jù)汽車制造商提出的汽車梁技術(shù)要求和沖壓過程的三維模型，建立了工藝補(bǔ)充符合要求，利用UG的數(shù)值模擬。導(dǎo)入到Dynaform的三維模型，模型是由四邊形網(wǎng)格利用網(wǎng)格自適應(yīng)技術(shù)，然后檢查和修復(fù)的有限元模型，通過使用復(fù)制命令建立了沖床和模具的有限元模型。沖壓方向是根據(jù)實(shí)際情況調(diào)整，板料、壓邊圈、模具間隙和定位確定完成后，沖壓成形數(shù)值模擬的有限元模型如圖1。工藝因素對(duì)沖壓效果分析壓邊力對(duì)成形的影響。壓邊力沖壓過程一般可以用以下公式估算：FBHF=Aq〔1〕在方程〔1〕，F(xiàn)BHF是壓邊力〔N〕；A是壓邊和空白的接觸面積〔mm2〕；q是單位面積的壓邊力〔MPA〕；在DYNAFORM，靜摩擦系數(shù)為0.125，沖壓速度是5000mm/s，凸模和凹模之間的間隙為1.1T〔T是板材厚度〕，和下模固定不動(dòng)。進(jìn)行了數(shù)值模擬分析時(shí)分別壓邊力為四個(gè)數(shù)值：490kN，540kN，590kN，630kN。成形數(shù)值模擬中的極限圖是顯示在圖2中，壓邊力590kN。從圖2可以看出，該局部燙金后不開裂，但在邊緣發(fā)生起皺現(xiàn)象。這說明在這個(gè)位置使局部加厚材料的流動(dòng)是不充分的，這就是改良過程的必要性。厚度的最大和最小局部是在浪費(fèi)區(qū)，這對(duì)局部質(zhì)量無影響。最后，重點(diǎn)研究了零件沖壓后的有效面積，最大減薄率，最大增厚率等數(shù)據(jù)有效的是四種不同的壓邊力，如表1。從表1可以看出，最大減薄率逐漸增大，最大增厚率呈下降趨勢，而壓邊力是增加的。這兩個(gè)參數(shù)是板帶產(chǎn)品質(zhì)量評(píng)價(jià)指標(biāo)后形成的，但他們無法說明板材成型后厚度的均勻度。因此，本文的特點(diǎn)是成形后板材厚度平均厚度偏差的均勻度。平均厚度為所有節(jié)點(diǎn)的厚度的平均值的數(shù)值模擬。平均偏差是指每個(gè)節(jié)點(diǎn)的平均厚度之間的絕對(duì)偏差的平均值，和平均偏差的數(shù)學(xué)表達(dá)式，它是用來反映各節(jié)點(diǎn)厚度的分散度，即板材厚度的均勻度。從圖3可以看出，隨著壓邊力增加的局部，平均厚度逐漸減小，而平均偏差為逐步提高。這些局部正說明，每個(gè)節(jié)點(diǎn)的厚度分散度隨著壓邊力的增加而增加，而這局部的均勻成形后變得更糟。因此，滿足減薄和增厚的需求的情況下，我們可以選擇較小的壓邊力，提高在實(shí)際生產(chǎn)中形成均勻的局部后處理程序。沖壓速度對(duì)成形的影響。四數(shù)值模擬的分析程序中，沖壓速度分別為4000mm/s，4500mm/s，5000mm/s，5500mm/s進(jìn)行了研究沖壓速度對(duì)零件成形的影響，當(dāng)壓邊力是590kN。四的數(shù)值模擬程序的一些分析數(shù)據(jù)整理在表2。正如從表2可以看出，沖壓速度的增加，最大減薄率呈現(xiàn)增加的趨勢，在這個(gè)區(qū)間的峰值最大增厚。沖壓速度的增加，局部的平均厚度逐漸變厚的沖壓后。在低沖壓速度區(qū)間，平均偏差值較大時(shí)，沖壓速度大，價(jià)值減少。說明在高沖壓速度的條件下，沖壓后才能更好的均勻性。因此在實(shí)際生產(chǎn)中會(huì)變薄和增厚的需求的情況下，我們可以選擇處理程序具有較高的沖壓速度以提高形成根據(jù)沖