材料期刊网

Influential Factors on Electromagnetic Properties of Selected 3D Reticulated Ceramics

Qing GONG , Xiaoming CAO , Jinsong ZHANG , Zheng FANG

材料科学技术（英文）

3D reticulated ceramics (3DRCs) with the composition containing SrFe12O19-SiC-TiO2 were prepared by a replication process with polyurethane sponges as the template in ceramic slurry. The electrical conductivity, dielectric and magnetic parameters of 3D reticulated ceramics (3DRCs) were measured with changes in cell size of the sponges, contents in the slurry and sintering temperature in this paper. Discussions about the influential factors of those parameters were focused on their electrical conductivity. The experimental results indicated that the electrical conductivity of 3DRCs raised with the increase of cell size, SiC/SrO·6Fe2O3 with weight ratio and sintering temperature. X-ray diffractions and SEM were used to investigate the relationship between electrical conductivity and sintering temperature. Deoxidizing reactions of SrO·6Fe2O3 caused the increasing electrical conductivity. The real part of permittivity (ε') and imaginary part of permeability (μ'') raised with the increase of electrical conductivity (σ). The imaginary part of permittivity (ε'') has a maximum at 100S/cm with the increase of sigma, and the real part of permeability (μ') changes slightly with the increase ofσ. When sigma is at the range of 10-4 S/cm to 100 S/cm (a semi conductive state), both the imagine part of permittivity and permeability raises with increasing sigma, therefore, the 3DRCs present their high electromagnetic loss properties.

关键词: 3D reticulated ceramics , null , null , null

A prediction of the excess partial molar free energies of MgCl2 in the KCl-MgCl2-LiCl molten salt system containing MgCl2 below 0.5 from thermodynamic properties of binary systems

Quanru ZHANG , Yuangao LI , Zheng FANG

材料科学技术（英文）

The thermodynamical properties of MgCl2 in KCl-MgCl2-LiCl molten electrolytes containing MgCl2 below 0.5 (mole fraction, the same below) have been determined from the interchange energies of two binary systems KCl-MgCl2 and LiCl-MgCl2, by means of a model on the assumptions that the electrolytes in the solution are treated as independent particles instead of their ion forms and the interchange energy between the component pair KCl-LiCl is ignored when compared with those of component pairs KCl-MgCl2 and MgCl2-LiCl. The interchange energies, omega(KCl-MgCl2) and omega(MgCl2-LiCl) are obtained as -70000 and -13800 J.mol(-1), from the corresponding binary solutions, respectively.

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3 0CrMnSi 2A钢飞机主梁疲劳断裂分析

马康民 , 宣建光 , 康进兴

材料工程 doi:10.3969/j.issn.1001-4381.2001.10.012

用扫描电镜观察了某型飞机机翼主梁的疲劳断口,用疲劳条带估算了裂纹扩展寿命,并用Zheng-Hirt公式估算出裂纹尖端应力强度因子范围,估算结果与实验测定值十分接近,从而为研究老龄飞机的使用寿命,进行了有益的探索.

关键词: 机翼主梁 , 30crMnSiNi2A , 疲劳裂纹扩展寿命

1998 COMPREHENSIVE TABLE OF CONTENTS

中国腐蚀与防护学报

N。1Atmospheric Corrosivlty for Steels………………………………………………… .LIANG Caideng HO[I i。-tat（6）Caustic Stress Corrosion Cr。king of Alloy 800 Part 2.The Effect of Thiosul执e……………………………………… KONG De-sheng YANG Wu ZHAO Guo-zheng HUANG De.ltL。ZHANG Yu。。he CHEN She。g-bac（13）SERS slid E16CttOCh6iniC81 Stlldy Of Illhibit1Oli M6ch＆tllsth Of ThlollY68 Oil ITOll ID H....

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Monte Carlo simulation of angular distribution and fractionation in the zero-fluence isotope sputtering

Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms

A static Monte Carlo simulation program has been used to study the influence of primary and secondary knock-on atoms on the angular distribution and the fractionation, for zero-fluence sputtering of Mo-92-Mo-100. At 10 keV Xe ion energy, calculations show that significant depth-dependent momentum asymmetry exists in the near-surface region, as in Refs. (L.P. Zheng, R.S. Li, M.Y.LI, Nucl. Instr, and Meth. B 100 (1995) 490; L.P. Zheng, M.Y. Li, Nucl. Instr. and Meth. B 114(1996) 28). The calculations also show that at the polar emission angle range between 0 degrees and 90 degrees the probabilities of the sputtered primary knock-on atoms for Mo-92 and Mo-100 are small (6.1% for Mo-92 and 6.6% for Mo-100), especially, between 0 degrees and 30 degrees they are very small (2.5% for Mo-92 and 2.8% for Mo-100). At 0.1 keV Ar ion energy, the calculations show that partial momentum flux ratios, for the primary and the secondary knock-on atoms, deviate far from one, through marker plane 1 (about an atomic layer distance from the surface). (C) 1998 Elsevier Science B.V. All rights reserved.

关键词: mo-92-mo-100;targets

New criteria of glass forming ability, thermal stability and characteristic temperatures for various bulk metallic glass systems

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

Six mathematical criteria used for quantitatively measuring their glass forming ability, thermal stability and characteristic temperatures (temperature of glass transition T-g, crystallization onset T-x and liquidus T-l) of various bulk metallic glasses (BMGs) have been proposed in this article. It is found that the criteria are suitable for evaluating these quantities for BMGs. The estimated results are better than those calculated by Fang et al.'s models and Lu et al.'s gamma criterion, but our analyses indicate that these criteria, defined by the data (Pauling electronegativity xi, atomic radius ri, electron concentration ni and melting temperature T-mi) easily found in literatures, still need to be further refined in future research for shortcomings of the parameters. (C) 2007 Elsevier B.V. All rights reserved.

关键词: bulk metallic glasses;glass forming ability;thermal stability;supercooled liquid regions;mechanical-properties;amorphous-alloys;transition temperature;bond parameters;strength;binary;widths;ag

Fe80Si9B11非晶合金薄带热膨胀特性和结构弛豫分析

李红 , 孙克 , 李艳萍 , 石毅 , 郭金花 , 卢志超

金属功能材料

提出了采用推杆式热膨胀仪测试非晶合金薄带热膨胀特性的新方法.分析了Fe80Si9B11非晶薄带的热膨胀曲特性和非晶合金晶化过程.根据R.G.Zheng理论分析了结构弛豫中自由体积比变化,发现自由体积比曲线出现双峰.结合晶化前发生相分离的理论分析了这种变化的原因.分析表明:铁基非晶Fe80Si9B11晶化过程中先形成α-Fe(Si)相,再析出Fe3B、二次α-Fe(Si)相.晶化前先发生相分离,自由体积比增大,然后析出结晶相α-Fe(Si),自由体积比降低.随温度升高,B偏聚,自由体积比增大,随后析出Fe3B、二次α-Fe(Si)相,自由体积比降低.

关键词: 铁基非晶薄带 , 热膨胀系数 , 自由体积比 , 结构弛豫

ATOMIC FORCE MICROSCOPY OBSERVATION OF MAGNETRON SPUTTERED ALUMINUM-SILICON ALLOY FILMS

金属学报(英文版)

粒裕希停桑谩。疲希遥茫拧。停桑茫遥希樱茫希校佟。希拢樱牛遥郑粒裕桑希巍。希啤。停粒牵危牛裕遥希巍。樱校眨裕裕牛遥牛摹。粒蹋眨停桑危眨停樱桑蹋桑茫希巍。粒蹋蹋希佟。疲桑蹋停?##2##3##4##5ATOMICFORCEMICROSCOPYOBSERVATIONOFMAGNETRONSPUTTEREDALUMINUM-SILICONALLOYFILMSJ.W.Wu,J.H.FangandZ.H.Lu(NationalLaboratoryofMoleculeandBiomoleculeElectronics,SoutheastUniversity,Nanjing210096,ChinaManuscriptreceived27October1995)Abstrcat:Twodifferentsurfacemorphologycharacteristicsofmagnetronsputteredaluminumsilicon(Al-Si)alloyfilmsdepositedat0and200℃wereobservedbyatomicforcemicroscopy(AFM).Oneisirregularlyshapedgrainsputtogtheronaplane.TheotherisirregularlyshapedgrainsPiledupinspace.Nanometer-sizedparticleswithheightsfrom1.6to2.9nmwerefirstobserved.Onthebasisoftheseobservationsthegrowthmechanismofmagnetronsputteredfilmsisdiscussed.Keywords:magnetronsputtering,Al-Sialloy,surfacemorphology,atomicforcemicroscopy,filmgrowthmechanism1.IntroductionTheuseofaluminumalloys[1,2],inparticularAl-Si,isacommonfeatureinmanysinglelevelandmultilevelinterconnectionschemesadoptedinthemanufactureofmicroelectronicdevicesbecauseofseveraldesirableproperties.TheAl-Sigrainmorphology(size.geometryanddistributionofgrainsisassociatedwithstepcoverage[3],electromigration[4]andinterconnectsresistivity[5]etc..Thus,characterizationofAl-Sialloysurfacemorphologyisveryimportant,especiallywhenintegratedintensityincreasesandlinewidthsof0.3to0.5μmbecomecommon.Inthepasttwentyyears,theAl-Sialloysurfacemorphologywhichaffectsthereliabilityofmicroelectronicdeviceshasbeenwidelyinvestigatedbyscanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM)etc.[5-7].However,SEMandTEMhavetheirlimitationorinconvenience,forexample,theverticalresolutionofSEMisnothighandTEMneedscomplexsamplepreparation.Recently,anewgrainboundaryetchingmethodwasproposed￣[8]whichalsoneedstroublesomechemicaletching.Atomicforcemicroscopy(AFM),sinceitsemerging,hasbecomemoreandmoreusefulinphysics,chemistry,materialsscienceandsurfacescience,becauseofitshighresolution,easeofsamplepreparationandrealsurfacetopography.Recently,discussion[9,10]waspresentedonhowAFMwillplayaroleinsemiconductorindustry.Asaresponsetothisdiscussion,weusedAFMtoinvestigateAl-SialloysurfacemorphologyandhaveobtainedsomeresultswhichcannotberevealedbySEMorTEM.ThisindicatesthatAFMisagoodcharacterizationtoolinsemiconductorindustry.2.SamplePreparationInourexperiments,aluminumwith30ppmsiliconwassputteredonsiliconsubstrateinbatchdepositionmodeAllthreefilmswiththicknessof1.6μmweredepositedusinganargonsputteringpressureof4.2×10￣-3Pa.TheotherdepositionparametersaredescribedinTable1.Thesubstratewascleanedusingstandardpremetallizationcleaningtechniquespriortofilmdeposition.3.ExperimentalResultsandDiscussionTheAFMmeasurementswereperformedonacommercialsystem(NanoscopeIII,DigitalInstruments,SantaBarbara).Thetipismadeofmicrofabricatedsiliconnitride(Si_3N_4)Itisattachedtoa200μmcantileverwithaforceconstantofabout0.12N/m.Beforethesurfaceofsamplewasexamined.agoodtipwithananometer-sizedprotrusionatitsendwasselectedbeforehand,whichcanbeobtainedbyimagingtheatomicstructureofmicasubstrateandagoldgrid.AtypicaloperatingforcebetweenthetipandAl-Sisamplesurfaceisoftheorderof10￣-8Nandallimagesweretakenatroomtemperatureinair.AtypicaltopographicviewoftheAl-SifilmsisshowninFig.1(allimagescansizeis5by5μma,bandcarerespectivelyforsample1,2,and3).FromFig.la,itcanbeseenthatirregularlyshapedgrainstiltinginvaryingdegreespileupinspace,andgroovesamongtheirregularlyshapedgrainsaredifficulttodecideatacertainarea(wedefineitascharacteristicA).Toourknowledge,onreportsonthesurfacemorphologyhavebeenpresentedbefore.InFig1b,however,irregularlyshapedgrainsassembleonaPlaneandgroovesamongtheirregularlyshapedgrainsareeasytodecide(wedefineitascharacteristicB),whichisinagreementwithmanypreviousreports[5-7].InFig.1c,bothcharacteristicA(arrowA)andcharacteristicB(arrowB)wereobserved.IndoingAFMexperiments,weselectedfivedifferentscanareastobeimagedforeachsampleandfoundthatallimagesofeachsamplearerespectivelysimilartoFig.1a,bandc.Also,wenotedthatthesurfaceofinFig.1a.WethinkthatdepositionparameterswillinfluenceAl-Sisurfacemorphology,andthetiltedgrainsmaybesusceptibletomicrocracking.Byreducingthescansizeareato2by2μm(Fig.2aandb).Weobtainedmanyidenticalresultsasdescribedabove,suchasirregularlyshapedgrainsetc.Forthefirsttime,wefoundnanometersizedparticlesonirregularlyshapedgrainsurfacewhichcannotberevealedbySEMbecausethediameterofthesenanoparticlesisabout10nmandtheheightofthesenanoparticlesisintherangeof1.6to2.9nm.Inimaging,wenotedthatrotatingthescandirectionandchangingthescanfrequencydidnotaffectthestructureofthesegrainsasshowninFig.2aandb,rulingoutthepossibilitythatscanninginfluencedtheshapeoftheseparticlesorcausedsomesimilarimagingartifacts.Also,wenotedthatthenanoparticleswerenotobservedontheslopesofthegrooves(Fig.2aandb).Thisphenomenoncanbeexplainedasfollows:thepotentialenergyattheslopeislargerthanthatelsewhere,sotheparticlesseemmorelikelytobedepositedontheseareaswithlowerpotentialenergy.Fig.2c,scansize250by250nm,isazoomtopographicimage(whiteoutlineinb).Itshowsunevendistributionofthenanoparticles.Andtheheightdifferenceofthenanoparticlesindicatesdifferentgrowingspeed.Wethinkbasedonthemorphologyofnanoparticles,thattheheightdifferenceandunevendistributionofthesenanoparticlesshowdifferentgrowingadvantageandindicatethatatomshaveenoughenergytomovetoasuitablegrowingspot.Theenergymaybefromthefollowingsources:surfacetemperaturefluctuation,stressdifferenceorcollisionbetweenhighspeedsputteredatoms.Thesenanoparticlesgoongrowingandformmanyirregularlyshapedgrains.AndtheseirregularlyshapedgrainsfurtherconnecteachotheraccordingtocharacteristicAorB,finallyformingtheAl-Sisurfacemorphology.4.ConclusionWecandrawthefollowingconclusionsfromtheabove.First,theexperimentalresultsshowedthatAFMisapowerfultooltoinvestigatethedetailsofAl-Sisurfacemorphologywhichcangreatlyenrichourknowledgeofthefilmgrowthmechanism.Second,depositionconditionsplayanimportantroleindeterminingtheAl-Sisurfacemorphology.Third,thetwoAl-Sisurfacemorphologycharacteristicsarethatirregularlyshapedgrainsassembleonaplaneandirregularlyshapedgrainstiltinginvaryingdegreespileupinspace.Fourth,forthefirsttime,nanoparticleswereobservedonirregularlyshapedgrainsurfacewhichsuggestedthatthefilmgrowthmechanismwasbyinhomogeneousnucleation.Acknowledgements-BeneficialdiscussionswereheldwithDr.ZhenandMr.Zhu.ThisworkwaspartiallysupportedbytheNationalNaturalScienceFoundationofChina.RFFERENCES｜｜1D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)127.2D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)131.3D.pramanikandA.N.Saxena,SolidStateTechnol.33(1990)73.4S.S.IyerandC.Y.Worg,J.Appl.phys.57(1985)4594.5J.F.Smith,SolidStateTechnol.27(1984)135.6D.GerthandD.Katzer,ThinSolidFilm208(1992)67.7R.J.WilsonandB.L.Weiss,ThinSolidFilm207(1991)291.8E.G.Solley,J.H.Linn,R.W.BelcherandM.G.Shlepr,SolidStateTechnol33(1990)409I.SmithandRHowland,SolidStateTechnol.33(1990)53.10L.Peters,SemiconductorInternational16(1993)62.##61D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)127.2D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)131.3D.pramanikandA.N.Saxena,SolidStateTechnol.33(1990)73.4S.S.IyerandC.Y.Worg,J.Appl.phys.57(1985)4594.5J.F.Smith,SolidStateTechnol.27(1984)135.6D.GerthandD.Katzer,ThinSolidFilm208(1992)67.7R.J.WilsonandB.L.Weiss,ThinSolidFilm207(1991)291.8E.G.Solley,J.H.Linn,R.W.BelcherandM.G.Shlepr,SolidStateTechnol33(1990)409I.SmithandRHowland,SolidStateTechnol.33(1990)53.10L.Peters,SemiconductorInternational16(1993)62.##A##BATOMIC FORCE MICROSCOPY OBSERVATION OF MAGNETRON SPUTTERED ALUMINUM-SILICON ALLOY FILMS$$$$J.W.Wu,J.H. Fang and Z.H.Lu (National Laboratory of Molecule and Biomolecule Electronics,Southeast University,Nanjing 210096, China Manuscript received 27 October 1995)Abstrcat:Two different surface morphology characteristics of magnetron sputtered aluminumsilicon(Al-Si)alloy films deposited at 0 and 200℃ were observed by atomic force microscopy(AFM).One is irregularly shaped grains put togther on a plane.The other is irregularly shaped grains Piled up in space. Nanometer-sized particles with heights from 1.6 to 2.9 nm were first observed. On the basis of these observations the growth mechanism of magnetron sputtered films is discussed.

关键词: :magnetron sputtering , null , null , null , null