钛的腐蚀与钝化机理电子理论研究

*刘贵立­(,110023)(2007918;20071117),,.,.,,.Cl,,,.Pd,,PdH,H,.:,,,PACC:7120,6820,8160*(:50671069),(:20060807,05L297)(:1072026100).­E-mail:[e-mail]11引言,,,,,.,,.,.,[1)7].,.,,,.21模型与方法2111(A-Ti),a=0129511nm,c=0146843nm[8].A-Ti.4974..1|Z|015cX-Y,,,Pd.,XYZ0145nm,0125nm0145nm.,;,.212..[9],,,..,[10,11].[12],Slater-Koster577200871000-3290P2008P57(07)P4441-05ACTAPHYSICASINICAVol.57,No.7,July,2008n2008Chin.Phys.Soc.1[13].Pd:5s24d8,Ti:4s23d2,O:2s22p4,Cl:3s23p5,H:1s1.Pd,Ti,O,Cl,HPd-s:-6191eV,Pd-d:-17166eV,Ti-s:-6104eV,Ti-d:-11104eV,O-s:-34102eV,O-p:-16172eV,Cl-s:-29119eV,Cl-p:-13178eV,H-s:-13160eV.-ss,-pp,-dd.31结果分析31112,,.Cl.Cl.2,d.(Cl),,,.,,.-25)-15eV-3)-7eV.3,(Cl),-25)-15eV,sp.-25)-15eV(Cl).2EF=-1119747eV..,,.,,.,(,),,.33121,.1)[14]Eb=E-EEl,(1)Eb,E,El..,,.,444257.2)[15]EESE=Eib-Eclb=[Ei-(n-1)El-Eil]-(Ecl-nEl)=Ei-Ecl-Eil+El.(2)3)[14]EESE=Eib-Eclb=[Ei-nEl-Eil]-(Ecl-nEl)=Ei-Ecl-Eil,(3)n,Ei,Ecl,El,Eil.Eib,Eclb.,,,.1(1)(Cl).-31016317eV,,.,,,.Cl,.1TiT-iO*T-i2OT-i3OT-iClEbindPeV-31016317-34216372-37417199-40719540-34112079*O,2O,3O,.2,,,.Cl,,Cl.2O2O3OClEESEPeV-3210055-6410882-9713223-3015762,,,,(,)..,d,,.,,.Cl,,Cl.,,.[8].3131Pd,,.,,.,,.,,,,.,,,,.,,[10].Pd,Pd,Pd.Pd,H(3).,PdH,.3PdHPdH()PdPdEESEPeV-716348-315544-1612260-21165163141,-1163V.,,,.,,0)200e-800kJPmol,44437:,,[8].,,,.,,,.,(25e+0109V,+20V).[16],,.,1.Pd,Pd,.Pd,T-iPd,[17,18].Pd.41结论11,,.21,,.Cl,.Cl,Cl.,,.31Pd,.PdH,H,.[1]MelekhovRK1988SovietMater.Sci.2170[2]KolmanDG1977Metall.Mater.Trans.12A2645[3]UedaM1992Corrosion179[4]BeenJ1999JOM621[5]YoungGAJr1994Corrosion12919[6]PaoPS1997Scr.Mater.111321[7]PoundBG1994ActaMetall.Mater.51551[8]ZhangXY,ZhaoYQ,BaiCG2005TitaniumAlloysandApplication(Beijing:ChemicalIndustryPress)p255(inChinese)[2005(:)255][9]HaydockR1980SolidStatePhysics35(NewYork:AcademicPress)p216[10]LiuGL2006ActaPhys.Sin.551983(inChinese)[2006551983][11]LiuGL,LiRD2006ActaPhys.Sin.55776(inChinese)[200655776][12]HarrisonWA1980ElectronicStructureandthePropertiesofSolids(SanFrancisco:Freeman)p551[13]SlaterJC,KosterGF1954Phys.Rev.9414986[14]LiuGL2007ActaMetall.Sin.43249(inChinese)[200743249][15]XiaoSX,WangCY,ChenTL1998TheApplicationoftheDiscreteVariationalMethodintheDensityFunctionalTheorytoChemistryandMaterialsPhysics(Beijing:SciencePress)p92(inChinese)[1998(:)92][16]ZhuRZ1989MetalCorrosion(Beijing:MetallurgicalIndustryPress)p21(inChinese)[1989(:)21][17]SchutzRW2003Corrosion591043[18]SedriksAJ1975Corrosion3160444457ElectronictheoreticalstudyonthecorrosionandpassivationmechanismofTimetal*LiuGu-iLi­(CollegeofConstructionalEngineering,ShenyangUniversityofTechnology,Shenyang110023,China)(Received18September2007;revisedmanuscriptreceived17November2007)AbstractTheatomicclustermodelsofthecrackinATiformedbydislocationaccumulationweresetup.TheelectronicstructureofTiwascalculatedbyusingrecursionmethod,andtheinfluenceofO,Cl,andPdontheelectronicstructureofTiwasstudied.Thecalculatedresultsshowthat,thetotaldensityofstatesnearFermilevelislowerdduetotheexistenceofO,whichleadstothedecreaseofthechemicalactivityofTi.ThebindingenergyofTiisreducedbyoxygen.TheaffinitybetweenOandTiislarge,soOiseasytoreactwithTitoformtheoxidefilm.ThestabilityofClinTiandtheaffinitywithTiarenotasgoodasO.ClisdifficulttosubstitutetheOatomonthesurfaceofTi,sotheoxidefilmofTiisverystable,thephenomenonofoverpassivationcannotoccur.Theenvironmen-tsensitiveembeddingenergyofPdinthecrackissmallerthaninATigrain,soPdiseasytodiffusetothecrackandmakestheenvironmentsensitiveembeddingenergyofHriseobviously,whichleadstotheweakeningofHdiffusiontothecrackandtheimprovementofthestress-corrosionresistanceofTi.Keywords:Ti,corrosion,passivation,electronicstructurePACC:7120,6820,8160*ProjectSupportedbytheNationalNaturalScienceFoundationofChina(GrantNo.50671069),theScienceResearchProgramofEducationBureauofLiaoningProvince,China(GrantNos.20060807,05L297)andtheScienceandTechnologyDevelopmentProgramofShenyang,China(GrantNo.1072026100).­E-mail:[e-mail]44457: