外文翻譯數(shù)控技術

南京大學畢業(yè)設計(論文)外文資料翻譯學院(系)：機械工程學院專業(yè)：機械工程及自動化姓名：學號：(用外文寫)外文出處：RiskAllocationinInfrastructure(用外文寫)Financing附件：1.外文資料翻譯譯文；2.外文原文。

附件1：外文資料翻譯譯文數(shù)控技術1國內(nèi)外數(shù)控系統(tǒng)發(fā)展概況隨著計算機技術的高速發(fā)展，傳統(tǒng)的制造業(yè)開始了根本性變革，各工業(yè)發(fā)達國家投入巨資，對現(xiàn)代制造技術進行研究開發(fā)，提出了全新的制造模式。在現(xiàn)代制造系統(tǒng)中，數(shù)控技術是關鍵技術，它集微電子、計算機、信息處理、自動檢測、自動控制等高新技術于一體，具有高精度、高效率、柔性自動化等特點，對制造業(yè)實現(xiàn)柔性自動化、集成化、智能化起著舉足輕重的作用。目前，數(shù)控技術正在發(fā)生根本性變革，由專用型封閉式開環(huán)控制模式向通用型開放式實時動態(tài)全閉環(huán)控制模式發(fā)展。在集成化基礎上，數(shù)控系統(tǒng)實現(xiàn)了超薄型、超小型化；在智能化基礎上，綜合了計算機、多媒體、模糊控制、神經(jīng)網(wǎng)絡等多學科技術，數(shù)控系統(tǒng)實現(xiàn)了高速、高精、高效控制，加工過程中可以自動修正、調(diào)節(jié)與補償各項參數(shù)，實現(xiàn)了在線診斷和智能化故障處理；在網(wǎng)絡化基礎上，CAD/CAM與數(shù)控系統(tǒng)集成為一體，機床聯(lián)網(wǎng)，實現(xiàn)了中央集中控制的群控加工。長期以來，我國的數(shù)控系統(tǒng)為傳統(tǒng)的封閉式體系結(jié)構(gòu)，CNC只能作為非智能的機床運動控制器。加工過程變量根據(jù)經(jīng)驗以固定參數(shù)形式事先設定，加工程序在實際加工前用手工方式或通過CAD/CAM及自動編程系統(tǒng)進行編制。CAD/CAM和CNC之間沒有反饋控制環(huán)節(jié)，整個制造過程中CNC只是一個封閉式的開環(huán)執(zhí)行機構(gòu)。在復雜環(huán)境以及多變條件下，加工過程中的刀具組合、工件材料、主軸轉(zhuǎn)速、進給速率、刀具軌跡、切削深度、步長、加工余量等加工參數(shù)，無法在現(xiàn)場環(huán)境下根據(jù)外部干擾和隨機因素實時動態(tài)調(diào)整，更無法通過反饋控制環(huán)節(jié)隨機修正CAD/CAM中的設定量，因而影響CNC的工作效率和產(chǎn)品加工質(zhì)量。由此可見，傳統(tǒng)CNC系統(tǒng)的這種固定程序控制模式和封閉式體系結(jié)構(gòu)，限制了CNC向多變量智能化控制發(fā)展，已不適應日益復雜的制造過程，因此，對數(shù)控技術實行變革勢在必行。2數(shù)控技術發(fā)展趨勢2.1性能發(fā)展方向高速高精高效化速度、精度和效率是機械制造技術的關鍵性能指標。由于采用了高速CPU芯片、RISC芯片、多CPU控制系統(tǒng)以及帶高分辨率絕對式檢測元件的交流數(shù)字伺服系統(tǒng)，同時采取了改善機床動態(tài)、靜態(tài)特性等有效措施，機床的高速高精高效化已大大提高。柔性化包含兩方面：數(shù)控系統(tǒng)本身的柔性，數(shù)控系統(tǒng)采用模塊化設計，功能覆蓋面大，可裁剪性強，便于滿足不同用戶的需求；群控系統(tǒng)的柔性，同一群控系統(tǒng)能依據(jù)不同生產(chǎn)流程的要求，使物料流和信息流自動進行動態(tài)調(diào)整，從而最大限度地發(fā)揮群控系統(tǒng)的效能。工藝復合性和多軸化以減少工序、輔助時間為主要目的的復合加工，正朝著多軸、多系列控制功能方向發(fā)展。數(shù)控機床的工藝復合化是指工件在一臺機床上一次裝夾后，通過自動換刀、旋轉(zhuǎn)主軸頭或轉(zhuǎn)臺等各種措施，完成多工序、多表面的復合加工。數(shù)控技術軸，西門子880系統(tǒng)控制軸數(shù)可達24軸。實時智能化早期的實時系統(tǒng)通常針對相對簡單的理想環(huán)境，其作用是如何調(diào)度任務，以確保任務在規(guī)定期限內(nèi)完成。而人工智能則試圖用計算模型實現(xiàn)人類的各種智能行為。科學技術發(fā)展到今天，實時系統(tǒng)和人工智能相互結(jié)合，人工智能正向著具有實時響應的、更現(xiàn)實的領域發(fā)展，而實時系統(tǒng)也朝著具有智能行為的、更加復雜的應用發(fā)展，由此產(chǎn)生了實時智能控制這一新的領域。在數(shù)控技術領域，實時智能控制的研究和應用正沿著幾個主要分支發(fā)展：自適應控制、模糊控制、神經(jīng)網(wǎng)絡控制、專家控制、學習控制、前饋控制等。例如在數(shù)控系統(tǒng)中配備編程專家系統(tǒng)、故障診斷專家系統(tǒng)、參數(shù)自動設定和刀具自動管理及補償?shù)茸赃m應調(diào)節(jié)系統(tǒng)，在高速加工時的綜合運動控制中引入提前預測和預算功能、動態(tài)前饋功能，在壓力、溫度、位置、速度控制等方面采用模糊控制，使數(shù)控系統(tǒng)的控制性能大大提高，從而達到最佳控制的目的。2.2功能發(fā)展方向用戶界面圖形化用戶界面是數(shù)控系統(tǒng)與使用者之間的對話接口。由于不同用戶對界面的要求不同，因而開發(fā)用戶界面的工作量極大，用戶界面成為計算機軟件研制中最困難的部分之一。當前INTERNET、虛擬現(xiàn)實、科學計算可視化及多媒體等技術也對用戶界面提出了更高要求。圖形用戶界面極大地方便了非專業(yè)用戶的使用，人們可以通過窗口和菜單進行操作，便于藍圖編程和快速編程、三維彩色立體動態(tài)圖形顯示、圖形模擬、圖形動態(tài)跟蹤和仿真、不同方向的視圖和局部顯示比例縮放功能的實現(xiàn)。科學計算可視化科學計算可視化可用于高效處理數(shù)據(jù)和解釋數(shù)據(jù)，使信息交流不再局限于用文字和語言表達，而可以直接使用圖形、圖像、動畫等可視信息?？梢暬夹g與虛擬環(huán)境技術相結(jié)合，進一步拓寬了應用領域，如無圖紙設計、虛擬樣機技術等，這對縮短產(chǎn)品設計周期、提高產(chǎn)品質(zhì)量、降低產(chǎn)品成本具有重要意義。在數(shù)控技術領域，可視化技術可用于CAD/CAM，如自動編程設計、參數(shù)自動設定、刀具補償和刀具管理數(shù)據(jù)的動態(tài)處理和顯示以及加工過程的可視化仿真演示等。插補和補償方式多樣化多種插補方式如直線插補、圓弧插補、圓柱插補、空間橢圓曲面插補、螺紋插補、極坐標插補、2D+2螺旋插補、NANO插補、NURBS插補(非均勻有理B樣條插補)、樣條插補(A、B、C樣條)、多項式插補等。多種補償功能如間隙補償、垂直度補償、象限誤差補償、螺距和測量系統(tǒng)誤差補償、與速度相關的前饋補償、溫度補償、帶平滑接近和退出以及相反點計算的刀具半徑補償?shù)?。?nèi)裝高性能PLC數(shù)控系統(tǒng)內(nèi)裝高性能PLC控制模塊，可直接用梯形圖或高級語言編程，具有直觀的在線調(diào)試和在線幫助功能。編程工具中包含用于車床銑床的標準PLC用戶程序?qū)嵗?，用戶可在標準PLC用戶程序基礎上進行編輯修改，從而方便地建立自己的應用程序。多媒體技術應用多媒體技術集計算機、聲像和通信技術于一體，使計算機具有綜合處理聲音、文字、圖像和視頻信息的能力。在數(shù)控技術領域，應用多媒體技術可以做到信息處理綜合化、智能化，在實時監(jiān)控系統(tǒng)和生產(chǎn)現(xiàn)場設備的故障診斷、生產(chǎn)過程參數(shù)監(jiān)測等方面有著重大的應用價值。2.3體系結(jié)構(gòu)的發(fā)展集成化采用高度集成化CPU、RISC芯片和大規(guī)?？删幊碳呻娐稦PGA、EPLD、CPLD以及專用集成電路ASIC芯片，可提高數(shù)控系統(tǒng)的集成度和軟硬件運行速度。應用FPD平板顯示技術，可提高顯示器性能。平板顯示器具有科技含量高、重量輕、體積小、功耗低、便于攜帶等優(yōu)點，可實現(xiàn)超大尺寸顯示，成為和CRT抗衡的新興顯示技術，是21世紀顯示技術的主流。應用先進封裝和互連技術，將半導體和表面安裝技術融為一體。通過提高集成電路密度、減少互連長度和數(shù)量來降低產(chǎn)品價格，改進性能，減小組件尺寸，提高系統(tǒng)的可靠性。模塊化硬件模塊化易于實現(xiàn)數(shù)控系統(tǒng)的集成化和標準化。根據(jù)不同的功能需求，將基本模塊，如CPU、存儲器、位置伺服、PLC、輸入輸出接口、通訊等模塊，作成標準的系列化產(chǎn)品，通過積木方式進行功能裁剪和模塊數(shù)量的增減，構(gòu)成不同檔次的數(shù)控系統(tǒng)。網(wǎng)絡化機床聯(lián)網(wǎng)可進行遠程控制和無人化操作。通過機床聯(lián)網(wǎng)，可在任何一臺機床上對其它機床進行編程、設定、操作、運行，不同機床的畫面可同時顯示在每一臺機床的屏幕上。通用型開放式閉環(huán)控制模式采用通用計算機組成總線式、模塊化、開放式、嵌入式體系結(jié)構(gòu)，便于裁剪、擴展和升級，可組成不同檔次、不同類型、不同集成程度的數(shù)控系統(tǒng)。閉環(huán)控制模式是針對傳統(tǒng)的數(shù)控系統(tǒng)僅有的專用型單機封閉式開環(huán)控制模式提出的。由于制造過程是一個具有多變量控制和加工工藝綜合作用的復雜過程，包含諸如加工尺寸、形狀、振動、噪聲、溫度和熱變形等各種變化因素，因此，要實現(xiàn)加工過程的多目標優(yōu)化，必須采用多變量的閉環(huán)控制，在實時加工過程中動態(tài)調(diào)整加工過程變量。加工過程中采用開放式通用型實時動態(tài)全閉環(huán)控制模式，易于將計算機實時智能技術、網(wǎng)絡技術、多媒體技術、CAD/CAM、伺服控制、自適應控制、動態(tài)數(shù)據(jù)管理及動態(tài)刀具補償、動態(tài)仿真等高新技術融于一體，構(gòu)成嚴密的制造過程閉環(huán)控制體系，從而實現(xiàn)集成化、智能化、網(wǎng)絡化。3智能化新一代PCNC數(shù)控系統(tǒng)當前開發(fā)研究適應于復雜制造過程的、具有閉環(huán)控制體系結(jié)構(gòu)的、智能化新一代PCNC數(shù)控系統(tǒng)已成為可能。智能化新一代PCNC數(shù)控系統(tǒng)將計算機智能技術、網(wǎng)絡技術、CAD/CAM、伺服控制、自適應控制、動態(tài)數(shù)據(jù)管理及動態(tài)刀具補償、動態(tài)仿真等高新技術融于一體，形成嚴密的制造過程閉環(huán)控制體系。附件2：外文原文NCtechnologydevelopmenttrends1NCsystemdevelopmentsathomeandabroadWiththerapiddevelopmentofcomputertechnology,thetraditionalbeginningofafundamentalchangemanufacturing,theindustrialdevelopedcountriesspenthugesumsofmoneyonthemodernmanufacturingtechnologyresearchanddevelopment,tocreateanewmodel.Inmodernmanufacturingsystems,CNCtechnologyisthekeytotechnology,whichcombinesmicroelectronics,computers,informationprocessing,automaticdetection,automaticcontrol,suchastheintegrationofadvanced,ahigh-precision,high-efficiency,flexibleautomation,andothercharacteristics,themanufacturingindustryFlexibleautomation,integrated,intelligentplaythepivotalrole.Atpresent,NCtechnologyisundergoingafundamentalchange,fromaspecialclosed-loopcontrolmodetogeneral-purposereal-timedynamicopenallclosed-loopcontrolmode.IntheintegratedonthebasisoftheCNCsystemsultra-thin,ultra-light;onthebasisoftheintelligent,integratedcomputers,multimedia,fuzzycontrol,neuralnetworkandothertechnicaldisciplines,NCsystemtoachievehigh-speed,high-precision,Efficientcontrol,automaticprocessingcanbeamendedtoregulatecompensationandtheparametersforanonlineintelligentfaultdiagnosisandtreatmentofthenetworkbasedontheCAD/CAMandCNCsystemsintegrationasonemachinenetwork,makesthecentralgovernmentcentralizedcontrolofthegroupcontrolprocessing.Foralongtime,China''sCNCsystemfortraditionalclosedarchitecture,butonlyasanon-intelligentCNCmachinecontroller.Processvariablesbasedonexperienceintheformofpre-fixedparameters,processingproceduresbeforetheactualprocessingbyhandorthroughCAD/CAMandautomaticprogrammingsystemprepared.CAD/CAMandCNChavenofeedbackcontrollink,theentiremanufacturingprocessCNCisaclosedring-openingimplementingagencies.Inacomplexandchangingenvironmentundertheconditionsofprocessingtoolintheprocessofcomposition,workpiecematerial,spindlespeed,feedrate,toolpath,cuttingdepth,step,allowanceandotherprocessingparameters,notatthescenecircumstancesunderexternalinterferenceandreal-timedynamicrandomfactors,notbyrandomamendmentfeedbackcontrollinkCAD/CAMsettingsvolume,inturn,affecttheworkofCNCmachiningefficiencyandproductquality.Clearly,thetraditionalfixedCNCsystemthatcontrolledmodeandclosedarchitecture,limitingtheCNCtothedevelopmentofmoreintelligentcontrolvariables,cannolongermeettheincreasinglycomplexmanufacturingprocess,therefore,theCNCtechnologyinthepotentialforchangeinevitable.2NCtechnologydevelopmenttrends2.1Performancedevelopmentdirectionhigh-speedhigh-precisionefficientspeed,accuracyandefficiencyofmachinerymanufacturingtechnologyisthekeyperformanceindicators.Asaresultofthehigh-speedCPUchips,RISCchip,aswellasmulti-CPUcontrolsystemwithhigh-resolutiondetectoroftheabsoluteexchangedigitalservosystem,takenatthesametimeimprovethemachinedynamicandstaticcharacteristicsofeffectivemeasures,thehigh-speedhigh-precisionmachinehasbeenefficientgreatlyenhanced.Flexibleincludestwoaspects:CNCsystemitselfflexibility,NCsystemismodularindesign,functionalcoverage,canbecutandstrong,andeasytomeettheneedsofdifferentusers;groupcontrolsystemflexibility,withacontrolsystempursuanttotherequirementsofdifferentproductionprocesses,materialsflowandinformationflowautomaticallydynamicallyadjustedtomaximizetheirgroupcontrolsystemperformance.Processofcompositeandmulti-axistoreducetheprocesstimeforthemainpurposeofsupportingthecompositeprocessing,andaremovingtowardsmulti-axis,multi-functioncontrolofthedirectionofseriesdevelopment.NCMachineToolTechnologycompositereferstotheworkpieceinasinglemachineonafixture,throughanautomatictoolchange,rotatingspindleheadorturntable,andothermeasurestoaccomplishmultipleprocesses,multi-surfacemachiningcompound.AxisCNCtechnology,Siemens880-axiscontrolsystemforupto24axes.Real-timeIntelligentearlyforthereal-timesystemisusuallyrelativelysimpleidealenvironment,anditsroleistoschedulingtasks,toensurethatthetaskbecompletedwithinaspecifiedtimelimit.Andartificialintelligenceisusedtomodeltherealizationofmankind''svariousintelligentbehaviors.Tothedevelopmentofscienceandtechnologytoday,real-timesystemsandartificialintelligencecombinedwitheachothertowardsartificialintelligenceisareal-timeresponse,amorerealisticfieldofdevelopment,andalsointhereal-timesystemwithintelligentbehavior,themorecomplexapplicationdevelopment,resultingintheIntelligentreal-timecontrolofthisnewarea.NCtechnologyinthefield,real-timeintelligentcontroloftheresearchandapplicationofdevelopmentalongseveralmainbranches:adaptivecontrol,fuzzycontrol,neuralnetworkcontrol,expertscontrol,learningcontrol,feed-forwardcontrol.Forexample,inCNCprogrammingsystemwithexpertsystems,faultdiagnosisexpertsystemparametersautomaticallysetandtoolmanagementandautomaticcompensation,suchasadaptiveconditioningsystems,inhigh-speedprocessingoftheintegratedmotioncontrolaheadoftheintroductionofbudgetprojectionsandfunctional,dynamicFeedforwardfunctionsinpressure,temperature,position,velocity,control,fuzzycontrol,thecontroloftheNCsystemperformancegreatlyimproved,soastoachieveoptimalcontrolpurposes.2.2FunctionaldevelopmentdirectionTheuserinterfaceisgraphicaluserinterfacewiththeCNCsystemofdialoguebetweentheuserinterface.Sincedifferentusersinterfacerequirementsaredifferent,thusthedevelopmentoftheworkloadofgreatuserinterface,userinterfacesoftwaredevelopedintothemostdifficultpartof.AtpresentINTERNET,virtualreality,visualizationinscientificcomputingandmultimediatechnologies,suchastheuserinterfacehasputahigherdemand.Graphicaluserinterfacegreatlyfacilitatestheuseofnon-professionalusers,itcanbecarriedoutthroughthewindowandmenuoperation,easeofprogrammingandblueprintforrapidprogramming,three-dimensionaldynamicthree-dimensionalcolorgraphics,graphics,simulation,graphics,dynamictrackingandsimulation,andthedifferentdirectionsviewandpartialdisplayratioscalingfunctioncanbeachieved.visualizationinscientificcomputingvisualizationinscientificcomputingcanbeusedforefficientdataprocessingandinterpretationofdata,sothattheexchangeofinformationisnolongerlimitedtousingthewrittenwordandlanguage,andcandirecttheuseofgraphics,image,animation,videoandotherinformation.Visualizationtechnologyandvirtualenvironmenttechnology,tofurtherbroadentheapplicationareas,suchasadrawingdesign,virtualprototypingtechnology,whichshortenproductdesigncycles,improvingproductquality,reduceproductioncostisofgreatsignificance.NCtechnologyintheareasofvisualizationtechnologycanbeusedforCAD/CAM,suchasautomaticprogrammingdesignparametersautomaticallyset,toolcompensationandtoolmanagementofdynamicdataprocessinganddisplay,aswellastheprocessingofvisualsimulation,andotherpresentations.interpolation,andavarietyofmethodsofcompensationinterpolationmethodssuchasmultiplelinearinterpolation,circularinterpolation,cylindricalinterpolation,spaceellipticalsurfaceinterpolation,threadinterpolation,polarcoordinatesinterpolation,2D+2helicalinterpolation,NANOinterpolation,interpolationNURBS(non-uniformrationalB-splineinterpolation),splineinterpolation(A,B,Ckind),suchaspolynomialinterpolation.Avarietyoffunctionssuchascompensationgapcompensationverticalcompensationquadranterrorcompensation,andmeasurementsystemspitcherrorcompensation,andspeed-relatedfeedforwardcompensationandtemperaturecompensation,withnearlysmoothandexit,aswellastheoppositepointofthecutterradiuscompensation.high-performancePLCcontentscontentsperformanceCNCsystemPLCcontrolmodulecanbedirectlyusedladderdiagramorhigh-levellanguageprogramming,withintuitiveonlinedebuggingandonlinehelpfunction.ProgrammingtoolsincludethestandardusedlatheandmillingmachinePLCuserprogramanexample,usersmayPLCuserprogramstandardsonthebasisofeditorialchanges,thuseasilybuildtheirownapplications.applicationofmultimediatechnologyofmultimediatechnology-computers,audio-visualandcommunicationtechnology,andithasthecomputerintegratedvoice,text,imagesandvideoinformation.InNCtechnology,multimediatechnologycanbeappliedtoinformationprocessingintegrated,intelligent,real-timemonitoringsysteminthefieldandproductionequipmentfaultdiagnosis,monitoringofprocessparameterssuchasproductionhasasignificantvalue.2.3DevelopmentoftheArchitectureintegrationofahighlyintegratedCPU,programmableRISCchipsandlarge-scaleintegratedcircuitsFPGA,EPLD,CPLDandASICASICchipsthatcanimprovetheCNCsystemintegrationandhardwareandsoftwareoperatingspeed.ApplicationFPDflatpaneldisplaytechnologycanimprovedisplayperformance.Flat-paneldisplayswithhighscienceandtechnologycontent,lightweight,smallsize,lowpowerconsumptionandportabilityadvantagescanberealizedSupersized,acounterweighttotheemergingandCRTdisplaytechnology,displaytechnologyinthe21stcenturythemainstream.Applicationofadvancedpackagingandinterconnecttechnologies,semiconductorsandsurfacemounttechnologyintegration.Byincreasingthedensityofintegratedcircuits,reducingthelengthandnumberofinterconnectionproductstoreduceprices,improveperformance,reducecomponentsize,improvethereliabilityofthesystem.easytoimplementmodularhardwaremodularNCsystemsintegrationandstandardization.Accordingtovariousfunctionalrequirements,thebasicmodules,suchasCPU,memory,positionservo,PLC,theinputandoutputinterfaces,andcommunicationsmodules,makingthestandardSeriesproducts,throughfunctionalbuilding-blockapproachtocuttingthenumberofstepsandmodules,aNCsystematdifferentgrades.machineinterconnectionnetworkforremotecontrolofunmannedoperation.Machinethroughnetworking,canbeinanyonemachineontheothermachineprogramming,configuration,operation,operating,differentmachinecanbedisplayedonthescreeneachmachineonthescreen.general-opentheclosed-loopcontrolmodetoadoptacommoncomputercomponentBus,modular,open,embeddedarchitecture,easeofcutting,expansionandupgrading,canbecomposedofdifferentgrades,differenttypes,differentdegreeofintegrationCNCsystem.Closed-loopcontrolmodeisthetraditionalCNCsystemonlyforsingleclosed-open-loopcontrolmodeproposed.Themanufacturingprocessisamulti-variablecontrolandtheroleofintegratedprocessingcomplexprocess,includingprocessing,suchassize,shape,vibration,noise,temperatureandthermaldeformation,andotherfactors,therefore,toachievetheprocessofmulti-objectiveoptimization,Multivariablemustadopttheclosed-loopcontrol,real-timeprocessinginthedynamicadjustmentprocessvariables.Processingtheadoptionofopenuniversalreal-timeclosed-loopcontrolmodethewholedynamic,easyreal-timeintelligentcomputertechnology,networktechnology,multimediatechnology,CAD/CAM,servocontrol,adaptivecontrol,dynamicdatamanagementanddynamictoolcompensation,dynamicsimulationandotherhightechnologyintoone,atightclosed-loopmanufacturingprocesscontrolsystemtoachieveintegrated,intelligent,network-based.3PCNCnewgenerationofintelligentCNCsystemResearchandDevelopmentadaptedtothecurrentcomplexityofthemanufacturingprocess,withthestructureoftheclosed-loopcontrolsystem,anewgenerationofintelligentPCNCCNCsystemhasbecomepossible.PCNCNCintelligentsystemwillbeanewgenerationofintelligentcomputertechnology,networktechnology,CAD/CAM,servocontrol,adaptivecontrol,dynamicdatamanagementanddynamictoolcompensation,dynamicsimulationandotherhightechnologyintoone,atightclosureofthemanufacturingprocessCentralcontrolsystem.付：外文翻譯電火花加工電火花加工法對加工超韌性的導電材料（如新的太空合金）特別有價值。這些金屬很難用常規(guī)方法加工，用常規(guī)的切削刀具不可能加工極其復雜的形狀，電火花加工使之變得相對簡單了。在金屬切削工業(yè)中，這種加工方法正不斷尋找新的應用領域。塑料工業(yè)已廣泛使用這種方法，如在鋼制模具上加工幾乎是任何形狀的模腔。電火花加工法是一種受控制的金屬切削技術，它使用電火花切除（侵蝕）工件上的多余金屬，工件在切削后的形狀與刀具（電極）相反。切削刀具用導電材料（通常是碳）制造。電極形狀與所需型腔想匹配。工件與電極都浸在不導電的液體里，這種液體通常是輕潤滑油。它應當是點的不良導體或絕緣體。用伺服機構(gòu)是電極和工件間的保持0.0005~0.001英寸（0.01~0.02mm）的間隙，以阻止他們相互接觸。頻率為20000Hz左右的低電壓大電流的直流電加到電極上，這些電脈沖引起火花，跳過電極與工件的見的不導電的液體間隙。在火花沖擊的局部區(qū)域，產(chǎn)生了大量的熱量，金屬融化了，從工件表面噴出融化金屬的小粒子。不斷循環(huán)著的不導電的液體，將侵蝕下來的金屬粒子帶走，同時也有助于驅(qū)散火花產(chǎn)生的熱量。在最近幾年，電火花加工的主要進步是降低了它加工后的表面粗糙度。用低的金屬切除率時，表面粗糙度可達2—4vin.(0.05—0.10vin)。用高的金屬切除率[如高達15in3/h(245.8cm3/h)]時，表面粗糙度為1000vin.(25vm)。需要的表面粗糙度的類型，決定了能使用的安培數(shù),電容,頻率和電壓值?？焖偾谐饘伲ù智邢鳎r，用大電流,低頻率,高電容和最小的間隙電壓。緩慢切除金屬（精切削）和需獲得高的表面光潔度時，用小電流,高頻率,低電容和最高的間隙電壓。與常規(guī)機加工方法相比，電火花加工有許多優(yōu)點。1.不論硬度高低，只要是導電材料都能對其進行切削。對用常規(guī)方法極難切削的硬質(zhì)合金和超韌性的太空合金，電火化加工特別有價值。2.工件可在淬火狀態(tài)下加工，因克服了由淬火引起的變形問題。3.很容易將斷在工件中的絲錐和鉆頭除。4.由于刀具（電極）從未與工件接觸過，故工件中不會產(chǎn)生應力。5.加工出的零件無毛刺。6.薄而脆的工件很容易加工，且無毛刺。7.對許多類型的工件，一般不需第二次精加工。ElectricaldischargemachiningElectricaldischargemachininghasprovedespeciallyvaluableinthemachiningofsuper-tough,electricallyconductivematerialssuchasthenewspace-agealloys.Thesemetalswouldhavebeendifficulttomachinebyconventionalmethods,butEDMhasmadeitrelativelysimpletomachineintricateshapesthatwouldbeimpossibletoproducewithconventionalcuttingtools.Thismachiningprocessiscontinuallyfindingfurtherapplicationsinthemetal-cuttingindustry.Itisbeingusedextensivelyintheplasticindustrytoproducecavitiesofalmostanyshapeinthesteelmolds.Electricaldischargemachiningisacontrolledmetalremovaltechniquewherebyanelectricsparkisusedtocut(erode)theworkpiece,whichtakesashapeoppositetothatofthecuttingtoolorelectrode.Thecuttingtool(electrode)ismadefromelectricallyconductivematerial,usuallycarbon.Theelectrode,madetotheshapeofthecavityrequired,andtheworkpiecearebothsubmergedinadielectricfluid,whichisgenerallyalightlubricatingoil.Thisdielectricfluidshouldbeanonconductor(orpoorconductor)ofelectricity.Aservomechanismmaintainsagapofabout0.0005to0.001in.(0.01to0.02mm)betweentheelectrodeandthework,prev