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SteamSteam,steam

    Steam

Shettyeta1./dZhejiangUnivSciA20089l9):1245-1250

    ;JournalofZhejiangUniversitySCIENCEA

    ;ISSN1673?565X(Print);ISSN1862-1775(Online)

    ;wwwzju.edu.cn~zus;wwwspringerlink.com

    ;E-mail:jZUS@zjueducn

    ;1245

    ;eamascoolantandlubricantinturningofmetalmatrixcomposites

    ;RavirajSHETTYt,RaghuvirPAI,VasanthKAMATH,ShrikanthS.RAO

    ;(1DepartmentofMechanicalandManufacturingEngineering,ManipalInstituteofTechnology,Karnataka,India)

    ;(2DepartmentofMechanicalEngineering,NationalInstituteofTechnology,Karnataka,India)

    ;E-mail:rrshetty2@rediffmail.com

    ;ReceivedSept.12,2007;revisionacceptedDec.25,2007

    ;Abstract:Greencuttinghasbecomefocusofattentioninecologicalandenvironrnentalprotection.Steamischeap.poilu

    ;tionfreeandecofriendly,andthenisagoodandeconomicalcoolantandlubricant.Steamgeneratorandsteamfeedingsystem

    ;weredevelopedtogenerateandfeedsteam.ComparativeexperimentswerecarriedoutincuttingAA606l-15vo1.%SiC(25p.m

    ;particlesize),withcubicboronnitride(CBN)insertKB

    90gradeundertheconditionsofcompressedair,oilwateremulsion,

    ;steamascoolantandlubricant.anddrycutting,respectively.Theexperimentalresultsshowthat.withsteamascoolantandlu

    ;bricant,gradualreductioninthecuttingforce,frictioncoefficient,surfaceroughnessandcuttingtemperaturevalueswereobserved.

    ;Further,therewasreductioninbuiltupedgeformation.Itisprovedthatuseofwatersteamascoolantandlubricantisenviron

    ;mentallyfriendly.

    ;Keywords:Metalmatrixcomposites(MMCs),Turning,Cuttingforce,Thrustforce,Frictioncoefficient,Surfaceroughness,

    ;Builtupedge(BUE)

    ;doi:l0.163l~zus.A072203Documentcode:ACLCnumber:TH14

    ;INTR0DUCT10N

    ;Thebenefitofusingcompositematerialsandthe

    ;causeoftheirincreasingadoptionistobelookedfor

    ;intheadvanmgeofattainingpropertycombinations

    ;thatcanresultinanumberofservicebenefits.Among

    ;theseare:increasedstrength,decreasedweight,

    ;higherservicetemperature,improvedwearresistance ;andhigherelasticmodule.

    ;Cuttingfluidisusuallyusedtoreducecutting ;force,lowercuttingtemperature,prolongtoollifeand ;enhancemachiningeciencyandsurfacefinish

    ;qualityduringmachining.Ingeneral,thebetterthe ;performanceofcuttingfluid,themorepollutantitis ;toenvironment.Inthe2lstcentury,withenvironment ;protectionawarenessenhancedandlawsandregula. ;tionsenforced,greencuttinghasbecomeageneral ;trendinmachining(Chen.1984).

    ;Inthe1990s.Podgorkvveta1.(1992)and

    ;Godelvskieta1.(1998)proposedanewandpollu- ;tion-freegreencuttingtechniquewithwatervaporas ;coolantandlubricantduringcuttingprocess.Further ;fluidjetassistedmachiningasahighlyeffective ;methodforcuttingOfcOnventiOnalmaterialshasbeen ;wellexplored(LiandSeah,2001:Li,1996a;1996b; ;KaminskiandAlvelid,2000;HungetaL,1997; ;Wleinert.1993:gandRajurkar,1997;Ma.

    ;zurkiewiczeta1.,1989;Shettyeta1..2006a;2006b; ;2006c;2007a;2007b;Shenoyeta1.,2006),inwhich ;fluids,suchasair,waterorsteam,mainlyactas ;transportationcarrierscarryingtheheatawayfrom ;thecuttingregion,andtheefficiencyofsuchacooling ;methodlargelydependsontheetpressureandflow ;rate.Theresultsshowthatthecuttingforceisreduced, ;thefrictioncoefficientandthesurfaceroughness ;valueRaaredecreased,andthecuttingtemperatureis ;lowered.Theobiectiveofthisstudyistodevelopan ;environmentalfriendlylubricantbaseduponanew ;conceptofhavingahighlubricitydespiteofpenetra- ;tionofsteam.Inthispaper,someexperimentsare ;donebasedonsteamascoolantandlubricant.The ;experimentalresultsindicatethatthenewmethodcan ;beappliedtoindustryforimprovingoperationenvi- ;ronmentandloweringcost.

    ;

    ;1246

    ;EXPERIMENT

    ;Shettyeta1./JZhejiangUnivSciA20089(9):1245-1250 ;Steamgeneratorandsteamfeedingsystem

    ;Thesteamgeneratorandsteamfeedingsystem ;aredevelopedinwhichjetflowparameters(pressure,

    ;flowrate)andcoolingdistance(itisthedistance ;betweennozzleandcuttingzone)arecontrollable. ;Figs.1aandlbshowthetopviewandfrontviewof ;steamgeneratorandsteamfeedingsystem,respec

    ;tively.

    ;(a)

    ;Fig.1Steamgeneratorandsteamfeedingsystem. ;(a)Topview;(b)Frontview

    ;Simulationofdistributionofvelocity

    ;Themainpartoftheexperimentalsetupconsists ;ofasaturatedsteamsupply,asuperheater,aservo ;valveandapressuregaugeforcontrollingthesupply ;pressure,a2mmexitdiameternozzlewithasteam ;flowmeterforsteamflowratemeasurements.The ;steamietinvestigateddischargesintotherakefaceas ;aonecomponent,i.e.,singlephasefluid.However,

    ;theflowgoesthroughaphasechangeandmixeswith

    component,hence,ithasdifferent ;airasanotherone

    ;constituentsatdifferentlocations(e.g.,iuststeamin ;thecoreregion).Massfractionsofthecomponentsof ;thejetvarythroughoutthejet.Inthepresentsimula

    ;tions,thesteamietandnecessaryboundarycondi. ;tionswerechoseninasimplifiedforlT1.Itwasas. ;sumedthatthesteamleavingthenozzlewaswetwith ;inletboundaryconditionscalculatedfrom ;wetequilibriumexpansion.Phasechangeswereig

    ;noredinmixingthewetsteamwiththesu~ounding ;air.Hence,thetheoreticalapproachtakentosolvethe ;steamietflowwasbasedupontheassumptionthatthe ;steamdropletairmixtureislocallyhomogeneous. ;Thevelocityofsteamietflowdirectlyinfluences ;lubricatingandcoolingeffect.Throughmeasuring ;velocityofnozzleindifferentlocationsinthecooling ;distance.thedistilbutionofvelocityismodeledin ;ANSYSwithdifferentcolorsstandingfordifferent ;valuesofvelocity.Figs.2aand2bshowvelocityand ;vectorplotofthesimulatedresults,respectively. ;(a)

    ;Fig.2(a)Velocityand(b)vectorplotofthesimulated ;results

    ;Cuttingexperiments

    ;Theselectedexpefimentalmaterialwasmanu

    ;facturedbystircastingprocess.Thematrixmaterials ;usedwas99.9%purealmninum.andl5vo1.%SiC

    ;particleswithanaveragesizeOf25p.mwereapplied ;asthereinforcementelement.Thespecimenswerein ;barshapesOf40mmdiameterand120mmlength. ;Thechemica1compositionofspecimenswasgivenin ;Table1.Turningmethodasmachiningprocesswas ;selected.TheexperimentalstudycarriedoutinPSG ;Al4llathef2.2kW1.Theselectedcuttingtoolwas ;

    ;Shet~eta1./JZhejiangUnivSciA20089l9):1245-1250 ;cubicboronnitride(CBN)insertKB90(ISOcode),

    ;formachiningofmetalmatrixcomposite(MMC) ;materials.TheISOcodesofcuttingtoolinsertandtool ;holderwereshowninTable2.Theselectedmachining ;parametersweregiveninTable3.Themachining ;processisconductedasdry,oilwateremulsions, ;compressedairandsteamcutting,andcompletedafter ;80sturningperiod.Thecuttingforceandthrustforce ;weremeasuredrespectivelybyusinganIEICOS ;DigitaltooldynamometershowninFig.3.Surface ;roughnesswasmeasuredusingTaylor/Hobson ;surtronic3+surfaceroughnessmeasuringinstrument. ;Examinationofbuiltupedgeandsurfaceroughness

    ;wasobservedinJEOLJSM6380LAAnalytical

    ;scanningelectronmicroscope(SEM).

    ;EXPERJMENTALRESUSANDDISCUSSION

    ;Inthispaper,tocomparetheeffectsofsteam,oil ;Table1Nominalchemicalcompositionofbasemetal ;(6061AIalloy)

    ;ElementWeightpercentage(%)

    ;Cu

    ;Mg

    ;Si

    ;Cr

    ;Al

    ;0-25

    ;1

    ;0.6

    ;0.25

    ;Balance

    ;Table2Detailsofcuttingtoolandtoolingsystem ;TypeSpecification

    ;ToolholderSTGCR2020Kl6:

    ;CTGPR12l2F1l

    ;Toolgeometry

;CBNtoolinsert(KB90)

    ;Approachangle:9l.:

    ;Toolnoseradius:0.4mm;

    ;Rakeangle:0.:

    ;Clearanceangle:7.

    ;TPGN160304LS;

    ;TPGN1l0304LS

    ;Conditionofmachining

    ;Machinetoolused

    ;Cuttingspeed(m/min)

    ;Feed(mm/r)

    ;Depthofcut(IYI1TI)

    ;Coolantused

    ;Coolantpressure(bar)

    ;Coolingdistance(mm)

    ;Turning

    ;PSGA141lathe(2.2kW)

    ;l50

    ;0.2

    ;0.5,1.0,1.5,2.0

    ;Steam.oilwater

    ;emulsions,compressedair,

    ;drycutting

    ;7

    ;30

    ;1247

    ;wateremulsions,compressedairanddrycuttingwere ;devoted.Thecuttingforces,thrustforcesandsurface ;roughnessvalueswereobtained,frictioncoe~cients ;ontherakefaceoftoolwereinvestigatedandbuiltup

    ;edgeformationwasobserved.Eachinvestigated ;subjectwasdevotedtodifferentheadingsasgiven ;be1ow.

    ;Cuttingforce()

    ;ItcanbeseenfromFig.4,whensteamascoolant ;andlubricantthemaincuttingforceisreduced,re

    ;spectively,about25%35%.15%-25%and5%-10%

    ;bycomparingwithdrycutting,oilwateremulsion ;andcompressedair.Becausesteamformshighve

    ;locityjetflowbythenozzleandinthecuttingzone,it ;willfillupthecapillariesoftoolchipinterfacein

    ;gaseousstateandhightemperaturesteamwillform ;boundarylubricationlayerofhighadsorptions~ength ;Asaresult,themaincuttingforceisremarkablyre

;duced.

    ;Thrustforce()

    ;Thethrustforcesofsteam,oilwateremulsions, ;compressedair,anddrycuttingwereillustratedfor ;800

    ;700

    ;600

    ;500

    ;400

    ;300

    ;200

    ;l00

    ;0

    ;Fig.3Forcemeasurementlayout

    ;00.51.01.52.02.5

    ;Depthofcut(mm)

    ;Fig.4Cuttingforcecomparison

    ;o.Joj警疆;u

    ;

    ;1248Shettyetal/dZhejiangUnivSciA20089(~:1245-1250 ;differentdepthsofcutinFig.5.Itwasobservedthat ;theminimumthrustforcewasobtainedbysteam ;application.Oilwateremulsionsproducedhigher ;thrustforcesandthedrycuttinggavemaximumvalue. ;Frictioncoefficient)

    ;Thefrictioncoefficientonrakefaceoftoolcan ;becalculatedbyusingmeasuredvalues(c,Pt)and

    ;Merchant’Stheory(Chen,1984)as

    ;..

    ;cosy+sin;/

    ;“=—————————.=———.cosy+siny’(1)

    ;whereiSthecoefficientoffriction,Pcthecutting ;force,Ptthethrustforceand),therakeangle.The ;cuttingforceandthrustforceweremeasuredbydy

    ;namometer.Fig.6showsthatthelowestfrictionCO

    ;efncientwascapturedbysteam.Assteamaccesses ;thecuttingzonewithhighvelocityjetflowandforlTIS ;muchsteadierboundarylubricationlayer.itelimi

    ;hatesallorpartadhesionoftoo1.chipfleshsurface, ;alleviatesseizurephenomenaandacceleratessub

    ;layerplasticflow.HencethefrictioncoecientiS

    ;decreasedeffectively.

    ;Z

    ;

;8

    ;&

    ;

    ;l

    ;Depthofcut(mm)

    ;Fig.5Thrustforcecomparison

    ;Depthofcutfmm,

    ;Fig.7Cuttingtemperaturecomparison

    ;Cuttingtemperature

    ;Thecuttingtemperaturewasmeasuredusing ;thermocoupleanditwasfoundtoincreasewithan ;increaseinthedepthofcut.Ingeneral,thecutting ;nuidmainlydependsonheatconvectiontoreduce ;thecuttingtemperature.Steamcanreducethecontact ;frictionoftoo1.chipinterfacewithhighefficiency ;lubricatingaction,andthenhasindirectlycooling ;effect.Steamtemperatureismuchlowerthanthe ;cuttingtemperature,SOsteamhassomefunctionof ;heatconvection.Undertheconditionsofdouble ;functionsofindirectcoolingandheatconvection,the ;cuttingtemperatureiSdecreasedmuchmore.Asitis ;seenfromFig.7,whensteamiSusedascoolantand ;lubricant.thecuttingtemperaturereducedtoabout ;20%.30%,40%,comparedwiththeotherconditions ;ofdrycutting,compressedairandoilwateremul

    ;Sjon.

    ;Surfaceroughness

    ;FromFig.8itcanbeseenthatundersteamlu

    ;bricationconditionsthesurfaceroughnessvaluesalso ;droppeddownsignificantly.

    ;.2

    ;15

    ;

    ;0

    ;1

    ;

    ;

    ;0

    ;0

    ;U

    ;00.51.01.52.02.5

    ;Depthofcut(mm)

    ;Fig.6Coefficientoffrictioncomparison ;Depthofcut(mFf1)

;Fig.8SurfaceroughnessvalueRa

    ;765432?

    ;0000000

    ;??????0

    ;65432?

    ??0IIo’0u? ;IIIT1

    ;1j.).J.4.l1lnu

    ;

    ;Shettyeta/./dZhejiangUnivSciA20089l9):1245-1250 ;Fig.9showstheSEMimagesofsurfacerough

    ;nessonA1SiCat2rfln3ofcutunderdrycutting,oil ;wateremulsions,compressedairandsteamcutting. ;Fig.9SEMimagesshowingthesurfaceroughnesson ;AlSiCat2mmdepthofcut.(a)Drycutting;(b)Oil ;wateremulsions;(c)Compressedair;(d)Steamcut

    ;ting

    ;Comparisonofchipsforms

    ;Theformofchipproducedisoneofthemajor ;parametersinfluencingproductivityinmetalcutting ;industry.Generally,therearetwogroupsofchip ;forms:acceptablechipsandunacceptablechips,for ;convenienceofhandling.Acceptablechipsdonot ;interferewiththeworkormachinetoolandcauseno ;problemsofdisposa1.Unacceptablechipsinterrupt ;regularmanufacturingoperation,astheytendtoen

    ;tanglethetoolandworkpieceandsafetyproblemsto ;operators.Entanglingchipscanharmthesurface ;finishandevenleadtounexpectedtoolfailure. ;Chipsformedduringthemachining(turning)of ;6061Aluminium15vo1.%SiCpcompositesinsteam ;cuttingunderdifferentcuttingconditionsfordifferent ;depthofcutareshowninFig.10.Itisclearthatthe ;chipshapesformedduringsteamascoolantandlu

    ;bricantinturningofA1/SiCMMCareintheformof

    ;sawtoothwithhighradiuscurlingcircleandbroken ;intosmallpieces.

    ;Built-upedgeformation

    ;Fig.11showsthebuiltupedge(BUE)during ;machiningofAlSiCpMMCsunderdry,compressed

    ;air,oilwateremulsionsandsteamascoolantat2mm ;depthofcut.Theturningoperationswereperformed ;consideringconstant150m/mincuttingspeed.0.20 ;mm/rfeedandfor80sturningperiod.FromFig.11.it ;canbeobservedthattheBUEsincreaseunderdry

;oi1waterCompressedSteamD

    ;epthofcutDry

    ;emulsionsa1r

    ;目嘲

    ;0.5mm

    ;l

    _e?????Ii)??_m ;la?—

    ;.0rnrfl

    ;(b)—?(f(j)_

    ;1.5rnrfl

    ;[c??lg_._?

    ;-

    ;2

    ;.0rnrfl

    ;d.)?_IK1)?_Kp)舅舅

    ;1249

    ;Fig.10Comparisonofchipsamplesunderdrycutting, ;compressedair,oilwateremulsionsandsteam ;Fig.11SEMimagesshowingtheBUEsonthecutting ;toolsaftermachiningAlSiCat2mmdepthofcut.(a)

    ;Drycutting;(b)Oilwateremulsions;(c)Compressed ;air;(d)Steamcutting

    ;condition,compressedair,oilwateremulsionstom

    ;paredtosteamascoolant.

    ;C0NCLUS10N

    ;f11Withsteamascoolantandlubricant,thecut

    ;tingforceisreducedrespectivelybyabout25%-35%, ;15%25%and5%-10%ascomparedwithdrycut

    ;ting,oilwateremulsionsandcompressedair;the ;frictioncoefficientandthesurfaceroughnessvalue ;aredecreasedrespectively;thecuttingtemperatureis ;lowered,too.

    ;(2)Steamascoolantandlubricantcanbean ;

    ;1250Shettyeta1./JZhejiangUnivSciA20089r9J:1245-1250 ;advantageinformingacceptablechips.

    ;(3)Whensteamisusedascoolantandlubricant, ;itpossessesbetterlubricatingactionbecauseofex- ;cellentpenetrationperformanceandformingoflow ;shearingstrengthlubricationlayer.

    ;(4)TherewasgradualreductioninBUEforma- ;tiohwithsteamascoolantinturningofAI-SiC ;MMCs.

    ;(5)Accordinglysteamascoolantandlubricant

    ;hastheadvantagesofbeingcheap,pollution-fleeand ;harmless.Thereisnoneedfordisposalorrecycling.It ;providesfundamentaltheoryforgreencutting. ;Reterences

    ;Chen.R.Y.1984.MetalCuttingPrinciple.MachineIndustry ;PublicationsChina.Hefei.China(inChinese). ;Godlevski,VA.,Volkov,A.V,Latysher,V.N.,Maurin,L.N., ;1998.Watersteamlubricationduringmachining.Tr. ;bologia.162(6):890.901.

    ;Hung,N.E,Yeo,S.H.,Oon,B.E.,1997.Oneffectofcutting ;fluidonthemachinabilityofmetalmatrixcomposites. ;JournalofMaterialsProcessingTechnology,67(1.3): ;l57.161.fdoi:1O.1016/S0924-0136(96)02836?1

    ;Kaminski,J.,Alvelid.B.,2000.Temperaturereductioninthe ;cuttingzoneinwater-jetassistedturning.JournaloJ ;MaterialsProcessingTechnology,106(1.3):68.73. ;fdoi:1O1016/S0924.0136(00)00640.3

    ;Li,X.P.,l996a.Studyoftheiet.flowrateofcoolinginma. ;chining.Part1.Theoreticalanalysis.JournalofMaterials ;ProcessingTechnology,62(1-3):149?l56.[doi:lO.1O16, ;0924.0136(95)02197.31

    ;Li,X.P.,l996b.Studyofthejet.flowrateofcoolinginma. ;chining.Part2.Simulationstudy.JournalofMaterials ;ProcessingTechnology,62(1?3):l57?165.doi:1O.1O16,

    ;0924.0136(95)02198.11

    ;Li,X.R,Seah,WK.H.,2001.Tbolwearaccelerationinrela. ;tiontoworkpiecereinforcementpercentageincutting ;metalmatrixcomposites.Wear,247(2):l61.171.fdoi:1O. ;1016/S00431648(OO)OO524x]

    ;Mazurkiewicz,M.,Kubala,Z.,Chow,J.,l989.Metalmachin- ;ingwithhighpressurewater-jetcoolingassistance--a ;newpossibility.EngineeringIndustries.111:7.12. ;Podgorkov,VV.1992.MethodofCuttinginApplication. ;PatentofUSSRl54972lMCIB23O(inRussia).

    ;Shenoy,B.S.,Shetty,R.,Pai,R.B.,Rao,S.S.,2006.Applica? ;tionofFite.elementAnalysisinOrthogonalCuttingof ;AluminiumMetalMatrixComposites.Proceedingsof ;InternationalConferenceonAdvancesinMechanical ;Engineering(ICAME2006),Chennai,India.

    ;Shetty,R.,Pal,R.B.,Rao,S…SShenoy,B…S2006a.Studyof

    ;ToolWearinTurningl5%SiCpReinforced606lAlu. ;miniumMetalMatrixCompositewithSteamasCoolant. ;ProceedingsofInternationalConferenceonAdvanced ;MaterialProcessingandCharacterization(APMC2006).

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