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Chapter1FundamentalsofCuttingAbstract1.1Basicdefinition1.2MaterialofthecuttingtoolProfessionalwordsinthischapter•Cuttingtool刀具•Velocity速度•Mainmotion主运动•Feedmotion进给运动•Resultantmotion合成运动•Referencesystem(frame)参考系（坐标）•Referenceplane基面•Cuttingedgeplane切削平面•Mainsectionplane主剖面•Normalsectionplane法剖面•Rakeangle(surface)前角（前刀面）•Reliefangle(surface，flank)后角（后刀面）•Cuttingedgeangle偏角•Inclinedangle刃倾角•Cuttingnose刀尖Teachingtime5hours(2hoursexperiment)•Basicrequirement:Conceptsanddefinitionofcuttingtoolgeometry(刀具几何角度定义）andreferencesystem（参考系）,usuallyusedcuttingtoolmaterial（常用刀具材料）•Teachingmethod:2-Dand3-Dfiguretoshowthedefinitionusinglathecuttingtool.MainCluesofthedevelopmentofcuttingtoolmaterial.Difficultyofthechapter•Explainthechangeoftoolworkingangles•Understandthechangeoftoolgeometryfromonesystemtoanothersystem（刀具角度在不同坐标系之间的变换)•Solution:Drawthe3-Dfigureofacuttingtoolandmarkthedifferentsurfaces,angles.Twopartsconcerningthefundamentalofmetalcuttingprocessareinvolvedinthischapter1Basicdefinition——includingbasicconceptsincuttingprocess,suchascuttingmotions(切削运动）,parameters(切削参数）,referenceframe（参考坐标系）,markedangles（标注角度）,cuttinglayerparameters2cuttingtoolmaterial——includingthenecessaryperformanceofcuttingtoolmaterial(hardness,wearresistance,strength,toughness,hothardness…),twokindsofnormalmaterialforcuttingtool(HSSandcarbidealloy)andtheothermaterial(coating,ceramicsdiamondandcubicboronNitride)Abstract1.1Basicdefinition1.1.2basicdefinitionofthecuttingregion1.1.3exchangeofthecuttingangles1.1.5cuttinglayerparametersandmode1.1.4workanglesofthecuttingtool1.1.1cuttingmotionandparametersForexample,inturning,theworkpiecerotates,thecuttingtoolmoveslongitudinally,themixtureofthetwomotionsformstheexternalcylindricalsurface.Therearethreesurfacescreatedinturnduringthenewsurfaceisforming（Figure1.1）：Fig1.1cuttingmotionsinturningSurfacetobemachined：meansthesurfaceinwhichthematerialistoberemovedMachiningsurface：meansthesurfaceisbeingmachinedbythecuttingedgeMachinedsurface：meansthesurfaceinwhichthematerialhasbeenremoved1.1.1cuttingmotionsandparameters1.1.1.1CuttingmotionThebasicmotionforamachinetoolincludeslinearmotionandrotationalmotion.Ifclassifiedaccordingtothefunctionsofthecuttingtoolinrelationwiththeworkpiece,theyarecalledthemainmotionandthefeedmotion,shownasFig.1.1（1）themainmotionthemainmotionrequiredtoremovethemetal.Usuallyithasthebiggestvelocity,andconsumesmostofthepower（2）thefeedmotionItbringsthenewmetalintocuttingconstantly.Itcanbecontinuousorinterrupted.Whenthemainmotionandthefeedmotiontakepartincuttingsimultaneously,thevelocityinonepointofthecuttingedgerelativetotheworkpieceiscalledresultantcuttingmotion,itssizeanddirectioncanberepresentedwithavectorve,shownasFig.1.3,anditequalsthevectorsumofthetwomotionsve=vc+vf(1.1)（3）resultantmotionandvelocityFig.1.2Theresultantvelocityincutting1.1.1.2Threeelementsincuttingve、f、aparecalledthethreeelementsincutting1000dn（1）CuttingspeedMostofthemaincuttingmotionsarerotationalmotion.Thevelocityinonepointoftherotatingbody(cuttingtoolorworkpiece)canbecalculatedusingthefollowingformulavc=m/sorm/min(1.2)whered－therotationaldiameterofonepointintheworkpieceorthecuttingtool（mm)n－numberofrevolutionpersecondorperminute(r/sorr/min).（r/sorr/min)Feedingspeedvfisthefeedinaunittime(m/sorm/min)Feedistherelativedisplacementbetweentheworkpieceandthecutteralongthedirectionoffeedingmotionperrevolutionorperstock(mm/r)。Formultipleteethcuttingtools,suchasmillingcutter,reamer,broach,gearhobetc.feedfzmaybemeasuredinmillimeterspertooltooth(mm/z).Obviously，vf=f·n=fz·z·nmm/sormm/min（1.3）（2）Feedingspeed,feedandfeedpertooth（3）BackengagementofthecuttingedgeForturningandplaning,thebackengagementofthecuttingedgeapisequaltothenormaldistancebetweenthemachinedsurfaceandtheworkpiecesurfacetobecut(mm).Forcylindricalturning,ap=（dw-dm）/2mm(1.4)Fordrillingap=dm/2mm(1.5)wheredm——diameterofmachinedsurface（mm）dw——diameterofworkpiecesurfacetobecut（mm）1.1.2Essentialdefinitionsfortheworkingpartsofcuttingtools1.1.2.1ThebasicelementsfortheworkingpartofcuttingtoolFig.1.3componentsoftypicalturningtool(1)Rakesurface(3)Cuttingedge(2)Flank(4)Toolnose(1)RakefaceRakefaceAristhesurfaceonwhichthechipactsdirectlyandwhichcantoolsthedirectionofthechipflowingout.Thepartadjoiningthemajorcuttingedgeisreferredtoasthemajorrakeface;thepartadjoiningtheminorcuttingedgeisreferredtoastheminorrakeface.（2）FlankThereareamajorflankandaminorflank.ThemajorflankAαisthesurfacewhichisoppositetothesurfaceontheworkpiece;theminorflankA’αisthesurfacewhichisoppositetothemachinedsurfaceontheworkpiece（3）CuttingedgeCuttingedgesaretheedgesengagedincuttingonrakeface.Therearemajorcuttingedgeandtheminorcuttingedge.Themajorcuttingedgeisanintersectinglinebetweentherakefaceandmajorflank,itperformstheprincipalworkofmetalremoval.Theminorcuttingedgeisanintersectinglinebetweentherakefaceandtheminorflank,itplaysasubsidiaryroleincutting.（4）ToolnoseThetoolnosemaybeanintersectingpointofmajorandminorcuttingedges,oranintermediatestraightlineoracirculararc.1.1.2.2Referencesystem（参考系）forthemarkeda