納米硼酸鑭添加劑的摩擦學(xué)性能研究

1、納米硼酸鑭添加劑的摩擦學(xué)性能研究程西云1鄧小桅1曹興進(jìn)1蔣松2(1重慶大學(xué)機(jī)械傳動國家重點(diǎn)實(shí)驗(yàn)室重慶4000442后勤工程學(xué)院油品應(yīng)用化學(xué)系重慶400016)程西云摘要:通過對含納米硼酸鑭粒子添加劑潤滑油的摩擦學(xué)性能試驗(yàn)研究發(fā)現(xiàn)納米硼酸鑭添加劑能改善滑動摩擦副的摩擦學(xué)性能、抗膠合能力及潤滑油的潤滑性能分析滑動摩擦副膠合失效后的表面形貌結(jié)合失效后滑動摩擦副表面XPS圖譜發(fā)現(xiàn)這是由于這種添加劑能在摩擦副表面形成吸附膜及聚合物膜且摩擦副表面有

2、滲硼層出現(xiàn)所致。關(guān)鍵詞:納米硼酸鑭添加劑滑動摩擦副摩擦學(xué)性能射儀測定納米粒子粒度和平均粒徑發(fā)現(xiàn)粒子直徑在10～70nm之間平均直徑為50nm通過X射線衍射圖譜分析表明該種粒子具有良好的分散性。1.3試驗(yàn)過程對表面膠合作系統(tǒng)研究的有OECD2IRG組織、SWRI組織以及Thomton組織它們采用的加載方式及加載時(shí)間間隔各不相同OECD2IRG組織采用試驗(yàn)過程中每加載一次則更換上相同的表面粗糙度的新試樣。SWRI組織則采用同一試樣一直做到發(fā)

3、生膠合為止。每次加載周期各研究組織也取得不一樣有的加載周期為60s即每次加載后摩擦副運(yùn)轉(zhuǎn)60s如不發(fā)生膠合則繼續(xù)加載。有的研究組織加載周期為3min也有的為10min。由于試驗(yàn)條件的限制在抗膠合性能試驗(yàn)中采用和SWRI組織相同的試驗(yàn)過程即在每次加載過程中不更換試樣加載周期為3min。中圖分類號:TH117.22文獻(xiàn)標(biāo)識碼:A納米粒子(100nm)是介于宏觀物質(zhì)與微觀原子或分子之間的過渡亞穩(wěn)態(tài)物質(zhì)具有特殊的表面效應(yīng)、界面效應(yīng)、小尺寸效應(yīng)和

4、化學(xué)活性因而備受國內(nèi)外學(xué)者重視納米材料在相關(guān)領(lǐng)域都得到了廣泛應(yīng)用。近年來有些學(xué)者采用這種粒子作為潤滑油添加劑并取得了部分效果12。本文以納米硼酸鑭作為潤滑油添加劑通過對基礎(chǔ)油及含302添加劑(硫磷極壓添加劑)潤滑油抗膠合性能的對比試驗(yàn)對這種添加劑作用下滑動摩擦副摩擦學(xué)性能作了系統(tǒng)研究利用失效前后表面XPS分析對這種添加劑的作用機(jī)理進(jìn)行了探討。2試驗(yàn)結(jié)果及討論2.1納米硼酸鑭對基礎(chǔ)油抗磨性能的影響將2%的納米硼酸鑭粒子分散到基礎(chǔ)油中試驗(yàn)轉(zhuǎn)

5、速為1500rm。試驗(yàn)結(jié)果如表1所示。1試驗(yàn)部分1.1試驗(yàn)設(shè)備磨損試驗(yàn)是在MQ2800型四球機(jī)上進(jìn)行的膠合試驗(yàn)在濟(jì)南試驗(yàn)機(jī)廠生產(chǎn)的MHK2500A型環(huán)塊式磨損試驗(yàn)機(jī)上進(jìn)行3。1.2試驗(yàn)材料試驗(yàn)用鋼球?yàn)?2.7mm的二級52100鋼球表面硬度HRC59261試環(huán)材料為GCr15鋼表面硬度為HRC60試塊材料為45#淬火鋼表面硬度HRC43表面粗糙度為0.33Λm。含硫磷極壓添加劑潤滑油采用市購302極壓添加劑按1%比例配制而成?；A(chǔ)油采用

6、350SN機(jī)械油。含納米硼酸鑭添加劑潤滑油也是按一定比例配制而成的。本文所用的納米添加劑為自制的通過動態(tài)激光光散表1納米硼酸鑭作用下長磨斑直徑對比基礎(chǔ)油基礎(chǔ)油加2%納米硼酸鑭負(fù)荷(N)磨損時(shí)間(min)長磨斑直徑(mm)392301.62588失效392300.38392600.40588300.66588600.76從表1可以看出基礎(chǔ)油中加入納米硼酸鑭后在相同載荷作用下長磨斑直徑減小了。采用基礎(chǔ)油潤滑時(shí)當(dāng)載荷達(dá)到588N時(shí)摩擦副已發(fā)生

7、膠合而加入納米硼酸鑭粒子后摩擦副仍能繼續(xù)工作。隨著磨損時(shí)間的加長長磨斑直徑變化不明顯這說明納米硼酸鑭粒子不僅能顯著提高摩擦副的抗磨能力而且能提高摩擦副的抗膠合能力。為了探討納米硼酸鑭添加劑的作用機(jī)理對磨斑表面進(jìn)行了表面能譜(XPS)分析以確定該種添加劑作用過程中的表面反應(yīng)生成物。圖1為磨痕表面的鑭元素及硼元素的XPS圖譜。從圖1a對磨痕表面鑭元素分析可以看出在電子結(jié)合能為836eV和852eV處存在凸峰表明磨斑表面收稿日期:200003

8、25基金項(xiàng)目:國家自然科學(xué)基金資助項(xiàng)目(項(xiàng)目編號:59905024)作者簡介:程西云(1966)男(漢)湖北博士后MECHANICALSCIENCEANDTECHNOLOGYTopicsAbstractsFoundrydescriptionmethodwhichadoptsthecharactersofvibra2tionsignaloflargemachine2sets.Basedonthisforecast2ingmethodsba

9、sedonstructuralpropertiesareconstructedaseriesofpredictionalgorithmsarealsopresented.Substantialresultswereobtainedinpredictingrunningconditionoflargerotatingmachineinpractice.Keywds:StructuralpropertiesPredictionRotorsF

10、aultdiagnosisMethodsfImprovingActionSensitivityofPunchPressPLCControlZHAOSheng2dunWANGEr2langSHANGChun2yangYANWu2chao(Xi′anJiaotongUniversityXi′an710049)P428Abstract:ThenecessityofimprovingactionsensitivityforpunchpressP

11、LCcontrolisanalysed.Accordingtore2quirementswhicharesatisfiedbyelectricalequipmentcon2trolsysteminJH23263punchpresspropertiesofPLCcontrolpracticalmethodsforefficientlyimprovingactionsensitivityofPLCcontrolofpunchpressare

12、putforward.Keywds:PunchpressPLCActionsensitivityExperimentalStudyontheTribologyPropertiesofLanthanumBateNanoparticleasAdditivesinLubricatingOilCHENGXi2yunDENGXiao2weiCAOXin2jingJIANGSong(ChongqingUniversityChongqing40004

13、4)P438Abstract:UsingTimkenmachinefour2ballmachinewestudiedexperimentallythewearscuffingresistantsofslidingfrictionpairsbyusingnanometerlanthanumbo2rateasadditivesinlubricatingoils.Theexperimentresultsshowthatthenanometer

14、lanthanumborateasadditivescanimprovethecharacteristicsoflubricatingoilsscuffingresistantofslidingfrictionpairs.BytheanalysisofwearsurfaceusingX2rayphotoelectronmicroscopy(XPS)wefoundthatthefrictionpairssurfacewerecovered

15、byad2sorptionfilmtribo2polymerfilms.WiththeincreasingoftheloadsthefrictionsurfacewerecoveredbyB2O3La2O3adsorptionfilmthisisthemainreasonwhythiskindadditivescanimprovethescuffingresistant.Wealsofoundthatthescuffingresista

16、ntsofslidingfrictionpairsdecreasewiththeincreasingoftheslidingvelocitythereisanainflexionpointastheslidingvelocityexceedthein2flexionpointscuffingresistantsofslidingfrictionpairsin2creasewiththeincreasingoftheslidingvelo

17、city.Keywds:NanometerlanthanumborateSlidingfrictionpairsScuffingAnApplicationofImageProcessingtoFaultDiagnosisfInternalCombustionEnginesXIAYongSHANGBin2liangZHANGZhen2renXUEMo2genGUOMin2fang(High2TechInstituteofXi′anXi′a

18、n710025)P432Abstract:Basedonimageprocessingwepresentanad2vancedfaultdiagnosisapproachforinternalcombustionen2gines.Thecylinderheadvibrationsignalsweredecom2posedwithwaveletpacketalgorithmthetime2frequen2cyimagesofthevibr

19、ationsignalswereobtained.Featuresofthevibrationsignalswereextractedinthetime2frequen2cyimages.Thefaultdiagnosismodelbasedonthetime2frequencyimage’smatchingcaneffectivelycarryoutdiag2nosisforthevalvetrainonafour2strokesix

20、2cylinderdieselengine.Itisnoteffectivetodiagnosewithgrayhis2togramsofthetime2frequencyimagesthereasonisgiven.Thedeviationofvibrationsignal’sphasewillleadtodeteriorationofdiagnosis.Thereforeattentionmustbepaidtothephasein

21、formationofthevibrationsignalwhenoneusesthediagnosismodel.Comparisonsofdiagnosisaremadebetweennoise2addedsignalsoriginalsignals.Thereislittleeffectonthediagnosingaftersignalswereaddedwithnoisesothismodelisgoodforengineer

22、ingap2plication.Keywds:ImageprocessingInternalCombustionEngineFaultdiagnosisVibrationWaveletpacketGrayhistogramAMethodfAnalyzingCrackGrowthFailureProbabilityConsideringtheRandomnessofInclusions′PositionofPMTurbineDiskXUL

23、ing2zhiWUXiao2liLUWen2lin(NorthwestPolytechnicUniversityXi′an710072)P440Abstract:Inthepaperamodelisestablishedaccordingtothedistributionofnon2metallicinclusionsinpowdermetal2lurgy(PM)alloys.Basedonthemodelafailureprobabi

24、li2tyanalysismethodofcrackgrowthispresentedwhichtakestheromnessofinclusions′positionintoconsidera2tion.APMdiskisusedasanexampleinthepaper.Keywds:PowdermetallurgydiskRomnessofposi2tionCrackcoalescenceFailureprobabilityOnL

25、ongTermPredictionofMechanicalFaultsBasedonStructuralPropertiesJIANGLin1GAODe2yuanXIEXiao2yan(1NorthwestP435PolytechnicUniversityXi′an710072)Abstract:Thepaperfocusesonthepredictionmethodbasedonstructuralproperties.Firstwe