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Chapter3Ceramics
陶瓷材料龍志慶理工大學材料科學與工程學院《材料概論》IntroductiontoMaterialsChapter3Ceramics
陶瓷材料重慶理工大2InorganicNon-metallicMaterials2InorganicNon-metallicMateri材料概論陶瓷雙語ppt課件陶瓷材料的概念與分類 Conceptandclassification陶瓷的結構StructureofCeramics陶瓷材料的制作工藝 Manufactureandprocessingtechnologies陶瓷材料的性能及應用 Propertiesandapplications2.1陶瓷材料的概念與分類2.11陶瓷的概念和分類
ConceptandClassifications
1.1概念
Concept陶瓷Ceramic:
燒過的粘土。是陶器
(pottery)和瓷器(porcelain)的總稱。定義:陶瓷指經過高溫處理所合成的無機非金屬材料(Inorganic&nonmetallicmaterials),簡稱無機材料。3.1Introduction1陶瓷的概念和分類3.1IntroductionWhatistheceramicTheword“ceramic”canbetracedbacktoGreekterm“keramos陶器”whichisrelatedtoanoldSanskrit(梵語)rootmeaning“toburn”.Canbedefinedasinorganiccompoundsmadebyheatingclayorothermineralmattertoahightemperatureatwhichtheypartiallymeltandbondtogether.Ceramiccanbedefinedasinorganic,nonmetallicmaterials.WhatistheceramicTheword“c陶器---瓷器比較表面效果制作材料燒制溫度敲擊聲音陶器---瓷器比較表面效果制作材料陶瓷之別陶器瓷器胎料普通的粘土瓷土(高嶺土)溫度一般<1000度一般>1100度表層不施釉或低溫釉多施釉吸水性胎質粗松,斷面吸水率高胎體堅固致密,斷面基本不吸水,敲之發出清脆的金屬聲響陶瓷之別陶器瓷器胎料普通的粘土瓷土(高嶺土)溫度一般<1009Ceramicsarerefractorypolycrystalline(多晶)compoundsHighlyinert(惰性);biocompatible(生物適應性的)Hardandbrittle(脆性)Highcompressivestrength(耐壓強度)Generallygoodelectricandthermalinsulators(絕緣)Goodaestheticappearance美觀9CeramicsarerefractorypolycUsuallycompound化合betweenmetallicandnonmetallicelementsAlwayscomposedofmorethanoneelementBondsarepartiallyortotallyionic,andmayhavecombinationofionic離子鍵andcovalentbonds共價鍵Majority多數hasionic(insaltcompounds)ormetallicandnonmetallicelements(asinoxidesAl2O3,MgO,SiO2)Usuallycompound化合betweenmet主要組分:硅酸鹽化合物在美國,陶瓷泛指硅酸鹽材料,又稱為傳統陶瓷或普通陶瓷。包括日用陶瓷、工業用陶瓷、一般玻璃、水泥、耐火材料等。
先進無機材料(advancedinorganicmaterials):
用氧化物、氮化物、硅化物、碳化物以至各種無機非金屬化合物經過
特殊的先進工藝制成的材料。
主要組分:硅酸鹽化合物1.2分類Classification12Ceramicstraditionalceramics:derivedandprocessedfromclayornonclaymineralsincludingrefractories(耐火材料),whitewares,cement(水泥),porcelain(瓷器),andstructuralclayceramics.advancedceramics:highpurity,bettermechanical,electrical,magnetic,andopticalproperties
1.2分類Classification12Cerami1.2.1傳統陶瓷Traditionalceramics:又稱普通陶瓷,主要是指以天然無機物如粘土等為主要原料、經高溫處理得到的制品,主要用于制造日用器皿、生活潔具等生活用具。瓷器Porcelain;Chinaware:細密的陶瓷器皿,質硬、半透明、白色、發聲清脆以及無孔,以長石(Feldspar)、石英(Quartz)和高嶺石(Kaolin)為基本原料經一次燒成。131.2.1傳統陶瓷Traditionalceramic1414TraditionalCeramics15TraditionalCeramics15藝術陶瓷16藝術陶瓷16材料概論陶瓷雙語ppt課件材料概論陶瓷雙語ppt課件材料概論陶瓷雙語ppt課件材料概論陶瓷雙語ppt課件1.2.2先進陶瓷Advancedceramics:又稱為精細陶瓷、新型陶瓷、高技術陶瓷、特種陶瓷等。New、technical、engineering、advancedceramics是指以精制的高純天然無機物或人工合成無機化合物為原料,采用精密控制的制造加工工藝燒結,得到的具有獨特性能的高功能陶瓷。211.2.2先進陶瓷Advancedceramics:AdvancedceramicsAdvancedceramicsare
developedformrathersimplechemicalcompounds,andadvancesinprocessingwhichhaveprovidedgreatercontrolovertheirstructures.Advancedceramic:thescaleoftherawmaterialsandmicrostructures,includingthecrystalgrains,crystalinterface,poresanddefectsisatthelevelofmicrons.先進陶瓷,從原料、顯微結構中所體現的晶粒、晶界、氣孔、缺陷等在尺度上都是處在微米級的水平。AdvancedceramicsAdvancedceraClassificationbasedonapplicationsAdvanced(New)CeramicmaterialsOxidesNitridesCarbidesAbrasivesRocketEnginesAbrasives研磨料
BioceramicsGasTurbiness燃氣渦輪機ResistanceHeating電阻加熱
ElectricalCuttingToolsSteelAdditives(Steel)CuttingToolsHighTemperaturesRefractoryBrickSubstrates基板CuttingTools(cermets)
耐火磚ForICChips
GlassAdditivescoatingsArmorCeramicMatrixCompositesNuclearFuelsReinforcingFibersClassificationbasedonapplicAdvancedCeramicsCuttingtoolsZirconiatoughenedalumina氧化鋯增強氧化鋁24AdvancedCeramicsCuttingtools25紅色陶瓷系列黑色陶瓷系列黃色陶瓷系列25紅色陶瓷系列黑色陶瓷系列黃色陶瓷系列密封環陶瓷系列26密封環陶瓷系列26點火頭系列27點火頭系列271.2.3先進陶瓷的分類組成composition:氧化物oxide、氮化物nitride、硅化物silicide、碳化物carbide
性能properties&applications:結構陶瓷structuralceramics、功能陶瓷functionalceramics281.2.3先進陶瓷的分類組成composition:2結構陶瓷:以力學、機械性能為主。Mechanicproperties功能陶瓷:利用材料的電、磁、光、聲、熱等性能及其耦合效應,如鐵電、壓電陶瓷、敏感陶瓷、快離子導體陶瓷等。主要從電性能上考慮有絕緣陶瓷、介電陶瓷、半導體陶瓷、導體陶瓷以至高臨界溫度的超導陶瓷。29結構陶瓷:291.3陶瓷的發展30陶器
瓷器(傳統陶瓷)高鋁質粘土和瓷土的應用釉的發明原料純化陶瓷工藝的發展
陶瓷理論的發展
先進陶瓷(微米級)納米陶瓷高溫技術的發展
顯微結構分析的進步性能研究的深入無損評估的成就相鄰學科的推動1.3陶瓷的發展30陶器瓷器(傳統陶瓷)高鋁1.4ApplicationsThermalBarrierCoatings:熱屏蔽涂層Lowthermalconductivity傳導性reducesmetaltemperatures311.4ApplicationsThermalBarriElectronicsPackaging電子封裝:Ceramics:ProvidehightemperatureperformanceandthermalexpansioncoefficientmatchtoSiliconHighthermalconductivitydesired32ElectronicsPackaging電子封裝:CeCeramicArmour裝甲33CeramicArmour裝甲3334Someotherexamples34Someotherexamples1.4陶瓷的發展趨向納米陶瓷nano-ceramic特性:原材料粉末rawmaterialspowder顆粒為納米級nano-levelgrains;微觀結構microstructures,晶粒grains,晶界interfaces,氣孔pores以及晶體缺陷defects同樣在納米級nano-level。351.4陶瓷的發展趨向納米陶瓷nano-ceramic35兩種晶型復合的復相陶瓷:同一化學組成的物質經適當的工藝控制,得到不同晶型和不同的顆粒形貌的復相陶瓷,達到自補強的目的。有機和無機復合的復相陶瓷:介于有機與無機材料之間,不需要高溫處理而獲得的一種新型材料。金屬陶瓷:金屬與陶瓷復合的復相陶瓷。36
兩種晶型復合的復相陶瓷:同一化學組成的物質經適當的工藝控3.2StructureofCeramicsCrystallinesolidscomposedofmetallicandnonmetallicmaterialsCeramicsarecrystalstructuresmadeofmetallicionsandInorganicmaterialsBondingiseitherpartiallyorcompletelyionic離子鍵.(還有共價鍵covalentbonds)
VariablesincludeThemagnitude量級oftheelectricalcharge電荷ontheions;Therelativesizeoftheions離子373.2StructureofCeramicsCrysPropertiesofCeramicsCorrosionresistance抗腐蝕,chemicalinertness惰性,thermalshockresistance抗熱震性,wear-resistance耐磨Electricalproperties:solidelectrolytesinexperimentalbatteriesandfuelcells燃料電池Otheruses:includeautomotivesensors,packagingforintegratedcircuits,electronic/opticaldevices,fiberoptics,microchips,andmagneticheads38PropertiesofCeramicsCorrosi3.2.1Structureofceramics普通陶瓷的結構Microstructureofordinaryceramics陶瓷是由金屬(類金屬)和非金屬元素之間形成的化合物,其中的原子(離子)主要以共價鍵或離子鍵相結合。陶瓷通常是一種多晶多相的聚集體。393.2.1Structureofceramics普通陶普通陶瓷的顯微結構主要由晶相、玻璃相、氣相及晶界構成。40普通陶瓷的顯微結構主要由晶相、玻璃相、氣相及晶界構成。40晶相
crystalphaseCrystalphase:themainphaseinceramicmaterials,andcomposedofsomesolidsolutionsandcompoundsh化合物.Itsstructureandmorphology形態decidethemicrostructure,propertiesandapplicationsofceramics.41晶相crystalphaseCrystalphase:IntroductionStructureofceramics:mostvariesfromrelativelysimpletohighlycomplex.Beingcompounds,ceramicsaremadeofdifferenttypesofatomsofvaryingsizes.42IntroductionStructureofceraSilicate硅酸鹽Thebasicstructureunit:SiO4tetrahedron四面體.Oxygen(O)and
silicon(Si)together
accountforabout
75%oftheearth’s
crust.43Silicate硅酸鹽ThebasicstructurTypes:>1000differentsilicatesoccurnaturally,dependingonthedifferentwaystheSiO4tetrahedracanbelinked.44Types:>1000differentsilicatClayClay:acomplexmixtureofsilicates.Silicates:arecomplexioniccompoundsthatareexceedinglynumerous數目眾多.Clays:have
sheetsoflinkedSiO4
tetrahedrawhichslideover
eachother,givingtheir
mineralsacharacteristicsoftfeeling.45ClayClay:acomplexmixtureoCharacteristicsoflayeredstructuresLayeredstructure:asalubricant潤滑劑,watercanpenetrate,producingamaterialthatispliable(柔軟的)andslippery.Whenheated:>1100oCinakiln(窯),thewaterinclayisremoved;thelayeredsheetsbondorlockintoarigid
structure.Thematerialwithsuchasolidstructureiscalledaceramic.46CharacteristicsoflayeredstrStructuresofsilicatesChainorringstructures:linkbysharingtheatomsintwocornersoftheSiO4tetrahedrons.Layeredsilicates:sharingthreecorneratoms.Suchas:talc滑石,kaolinite高嶺石clay,mica云母.Framework框架silicates:sharingfourcorneratoms.47StructuresofsilicatesChainoSilica二氧化硅Puresilica:threepolymorphs晶型cristobalite方石英tridymite鱗石英:hightemperaturequartz石英:lowtemperatureItisthebasicstructureforglassesandmanyceramics.48Silica二氧化硅Puresilica:threeStructures~PropertiesAtoms原子areheldstrongly:theatomsaredifficulttomoveorslipinrelationtoeachother.theductility延展性ofceramicsisverylowandtheyarebrittle.HighshearstressesLowductilityHighcompressivestrength抗壓強度Lowtensilestrength抗張強度.49Structures~PropertiesAtoms原Bendstrength:themaximumbendingstressintensionoffailure.MetalsVSceramics:atroomtemperature:theyarecompetitive;>850oC,metalsweakenwhileceramicsretainmuchoftheirstrength.Ceramics:goodheatresistance.alumina:1800oCsiliconcarbide:1700oCBendstrength:themaximumbenCeramicPhaseDiagramsMicrostructures:dependingonthecompositions,andthevariablesoftemperatureandpressure.Thedesiredmicrostructure:comingfromtheprocessing.Asthecompositionbecomesmorecomplex,themorethenumberofphasespresentthemselves.51CeramicPhaseDiagramsMicrosphasediagram相平衡狀態圖,相圖Thephasediagram,equilibrium,orconstitutionaldiagram:Themapthatshowsthedifferentcompositionsandthetemperaturesunderequilibriumconditions.(Mullite莫來石3Al2O3-2SiO2)52phasediagram相平衡狀態圖,相圖Thepha莫來石(或莫乃石)是一系列由鋁硅酸鹽組成的礦物統稱,
這一類礦物比較稀少。莫來石是鋁硅酸鹽在高溫下生成的礦物,人工加熱鋁硅酸鹽時會形成莫來石。天然的莫來石晶體為細長的針狀且呈放射簇狀。莫來石礦被用來生產高溫耐火材料。耐火度:
1800oC時仍很穩定,1810
oC分解為剛玉和液相莫來石是一種優質的耐火材料,它具有膨脹均勻、熱震穩定性極好、荷重軟化點高、高溫蠕變值小、硬度大、抗化學腐蝕性好等特點,目前主要有高純電熔莫來石、普通電熔莫來石、全天然鋁礬土精礦燒結莫來石和輕燒莫來石。適用于石油裂介爐、冶金熱風爐、陶瓷輥道窯、隧道窯、電瓷抽屜窯、玻璃坩堝窯及各種電爐的內襯,可直接接觸火焰53莫來石(或莫乃石)是一系列由鋁硅酸鹽組成的礦物統稱,
這一類3.2.2MicrostructuresofCeramicsPorosityandDensityMassdensity質量密度,whichusesthemassofamaterialdividedbyitsvolumereferstothistheoreticaldensityAtomicweightisamajorfactorindeterminingthedensityofamaterialClose-packed密實的metalsaremoredensethanopen-structuredmaterials.543.2.2MicrostructuresofCeramBrittleFractureofCeramics脆性斷裂Defects缺陷inceramicscandevelopduetointernalstresses(內應力)
andporosityThermalstressesduetoan-isotropicthermalexpansion(各向異性熱膨脹)tendtocrackweakgrainboundaries5596%densealuminaBrittleFractureofCeramics脆56PoresinpartiallysinteredAlumina部分燒結氧化鋁中的孔隙56PoresinpartiallysinteredGreendensity壓坯密度isthebulkdensity體積密度ofacompactpriortoitsdensification密實化.Inpreparingparticlesfortheproductionofpowderedmetalsorceramics,thepackingofsphericalshaped球形,monosized單一尺寸(0.1μm)particles,evenwhenvibrated振動tosettletheparticles,doesnotachieveadensitylevelmuchhigherthan60%.57Greendensity壓坯密度isthebulkDespitetappingorvibrating,theseparticlesdonotrearrangethemselvescompletelytoeliminate除去pores.Theoptimumdensityofsphericalparticlescanbereachedbyvaryingthesizedistributionofparticlestopermitsmallerparticles(50nmorless)tolocateintheinterstices(空隙)ofthelargerones.58
Despitetappingorvibrating,Ceramicsare,bynature,generallyporous孔隙的materialswithvaryingdegreesofporosity.Bulkdensity體積密度isusedinthisinstancetorefertoaceramic’sdensity,anditincludesthematerial’sporosityandthefactthatmostceramicscontainbothacrystallineandanoncrystallinephase.59Ceramicsare,bynature,generOpenporosity開口孔referstothenetworkofporesinamaterialthatisopentothesurfaceandintowhichaliquidsuchaswatercanpenetrate滲透ifthepartweresubmerged浸入init.Closedporosity閉口孔referstothoseporesthathavebecomesealedwithinthegrainstructure.60Openporosity開口孔referstothePoresaffectthestrengthofceramicsintwoways:First,theyproducestressconcentrations應力集中.Oncethestressreachesacriticallevel,acrackwillformandpropagate擴展.Second,poresreducethecross-sectionalareasoverwhichaloadcanbeappliedand,consequently,lowerthestressthatthesematerialscansupport.61PoresaffectthestrengthofcTheamount,size,distribution分布,andthecontinuity連續性ofvoids空隙inaceramicaretheprincipalfactorsthatdetermineitspropertiesIngeneral,porosityisdetrimental有害的toceramicsproperties.Grainboundary晶粒界線sliding,creeprate,andchemicalreactionsthatattacktheceramicorreduceitsmeltingpointaremoreadverse不利的conditionsproducedbyimpuritiesandporosity.62Theamount,size,distribution63收縮a收縮b收縮無氣孔的多晶體c說明:a:顆粒聚集b:開口堆積體中顆粒中心逼近c:封閉堆積體中顆粒中心逼近63收縮a收縮b收縮無氣孔的c說明:3.3CeramicProcessingTraditionalProcessingstructuralclayproductsandthewhitewares.Formation→Drying→Firing3.3CeramicProcessingTraditio成型Forming:將粉料直接或間接地轉變成具有一定形狀、體積和強度坯體,稱為素坯或生坯(roughcast)。成型的方法有很多,主要有可塑法、注漿法與壓制法。成型Forming:將粉料直接或間接地轉變成具有一定形狀可塑成型利用泥料的可塑性。將粉料與一定水份或塑化劑混合均勻,使之成為具有良好塑性的料團,再用手工或機械成型制成坯體。可塑成型利用泥料的可塑性。將粉料與一定水份或塑化劑混合均勻,注漿成型即漿料成型法,是將原料配制成膠狀漿料注入具有所需形狀的模具中成型,又可分為注漿成型和熱壓注漿成型。注漿成型即漿料成型法,是將原料配制成膠狀漿料注入具有所需形狀壓制成型將粉料填充在模型中,施加壓力,制成具有一定現狀和強度的坯體。分類:普通壓制成型和等靜壓制成型。適宜于干料(含水3~7%)或半干料(含水8~15%)。壓制成型將粉料填充在模型中,施加壓力,制成具有一定現狀和強度DryingandFiring/SinteringDrying:decreaselayersizeandspacingDryingandFiring/SinteringD常規燒結、熱壓燒結、氣焚燒結、放電等離子燒結、微波燒結造粒成型燒結加工檢測配料預燒根據確定的化學組成干壓、注模、注漿、擠塑等平整度材料性能粘接劑(PVA等),噴霧干燥Schematicillustration示意圖常規燒結、熱壓燒結、氣焚燒結、放電等離子燒結、微波燒結造粒成Sintering/firing梭式窯Sintering/firing梭式窯Therolesofclayminerals:Hydroplasticity含水塑性:byaddingwater,theclaysbecomeveryplastic.Dense&strongceramics:clayfuses融合ormeltsoverarangeoftemperatures;then,producingadenseandstrongceramicsduringfiringwithoutcompletemeltingsothatthedesiredshapeismaintained.Therolesofclayminerals:Hyd等離子放電燒結過程示意圖等離子放電燒結過程示意圖AdvancedCeramicProcessing制備工藝:不再以熔爐為主要燒結工具,如真空燒結、氣氛燒結、熱壓燒結、氣壓燒結等。性能:高強度、高硬度、耐腐蝕、導電、絕緣以及磁、電、光、生物相容性等。AdvancedCeramicProcessing制備工ChemicalprocessesSol-gelprocessingMeltprocessingProducingsingle-crystalmaterialsVaporprocessingDirectedmetaloxygenprocessChemicalprocesses固相法:包括熱分解法(thermaldecomposition);非晶合金退火結晶法(在玻璃轉變溫度下結晶);自蔓延高溫合成方法(制備金屬復合材料)。液相法:包括沉淀法;水解法;溶膠-凝膠法(通過水解金屬醇鹽或金屬無機鹽來合成氧化物的一種化學方法)。固相法:包括熱分解法(thermaldecomposi氣相法:包括氣相合成法;氣相熱分解法。機械法:球磨、振動磨、高能球磨、氣流粉碎。溶劑蒸發法:酒精干燥法、冷凍干燥法、熱石油工作法、噴霧工作法液相法和氣相法是制備超細粉的主要方法。氣相法:包括氣相合成法;氣相熱分解法。3.4PropertiesofCeramicsMechanicalpropertiesPhysicalpropertiesChemicalPropertiesFabricabilityOtherproperties3.4PropertiesofCeramicsMecMechanicalpropertiesNoyieldstrength:ceramicsdonotplasticallydeformbeforereachingtheirtensilestrength.Nopermanentelongationorreductioninarea:ceramicscannotbeplasticdeformedbyroomtemperature.MechanicalpropertiesNoyieldMechanicalpropertiesCompressivestrength:excellent,betterthanmetals,plastics,andcomposites.Hardness:highestintheengineeringmaterials.Thelong-termservicecharacteristicsofceramics:Fatigueresistanceandcreepstrength:goodTensilefatiguestrength:poor.MechanicalpropertiesCompressiSpecialMechanicalproperties:GoodincompressionVeryhighhardnessandgreaterstiffnessthanotherengineeringmaterials.Weakness:brittlenessSpecialMechanicalproperties:PhysicalpropertiesComparedtometals:ceramicsarelightweight,butlowdensitymayalsobeanindicatoroftoomuchporosityinaparticulargrade.Asastructuralmaterial:thedesignershouldselectaceramicwithhightheoreticaldensity(99%).PhysicalpropertiesComparedtoThemeltingpointsofceramics:areamongthehighestofallengineeringmaterials.Thethermalconductivityandelectricalconductivity:coveralargespectrum.Mostceramics:electricalinsulators,butsomearesemiconducting.Thermalexpansion:lowerthanmetalsandplastics.ThemeltingpointsofceramicsChemicalPropertiesResistanttochemicalattack:theengineeringceramics,aluminumoxide,siliconcarbide,zirconia,siliconnitride,andothers,areveryresistanttochemicalattackinawidevarietyofsolutes.ChemicalPropertiesResistantFabricabilityTheycannotbeplasticallydeformedtoshapesatroomtemperatures.Ceramicscannotbemeltedandcasttoshapeslikemetals,mostlybecauseoftheirhighmeltingtemperatures.Themachiningofceramicsissocostlythatitisnotanoptionformanymachineparts.FabricabilityTheycannotbeplOtherpropertiesWearResistanceThermalShockResistanceOtherpropertiesWearResistancApplicationsofCeramicsCanwithstandvolatileandhigh-
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