單質(zhì)硅微粒引起玻璃爆管的研究

單質(zhì)硅微粒引起玻璃爆管的研究

以輕量玻璃用于現(xiàn)代生活，可補(bǔ)償可再生。它是一個(gè)分離性的。這是一個(gè)非常關(guān)注的區(qū)域，而不是一個(gè)區(qū)域。這是一個(gè)基本的非點(diǎn)性特征。通過可再生訴訟中的訴訟，其內(nèi)容是可再生訴訟中的訴訟?！把由臁辈皇堑谝恍校堑诙小＿@是報(bào)告的。在中國，這是一個(gè)受歡迎的地方。Inordertoexplorethemechanismofthespontaneousbreakageoftemperedglass,sixcollectedsamplesofbrokentemperedglasshavebeeninvestigatedinthiswork.ItwasfoundthattherewasparticleontheoriginalareaofspontaneousbreakageofeachtemperedglassScanningelectronmicroscope(SEM)examinationofthesixparticlesdiscoveredthatfiveofthesamplescontainmonolithicsiliconparticles,andonlyoneofthemcontainssulfideparticles.Thesesurprisingresultsindicatethatoneoftheimportantcausesforspontaneousbreakageoftemperedglassisthemonolithicsiliconparticlesratherthanonlythenickelsulfideparticles,whicharecommonlyrecognizedasthecause.1er行業(yè)的清整Generally,thespontaneousbreakageintemperedglassisduetothestressconcentrationneartheimpureparticleslocatedinthetensilestresslayeroftheglass.Figure1showstheappearanceofthespontaneousbreakageofglass.Thecommoncharacteristicofspontaneousbreakageisabutterfly-shapedpieceattheinitiationzoneofthecracks.Inmanycases,impureparticlesthatleadtospontaneousbreakagecanbefoundinthemiddleofthebutterfly-shapedpiece.Impureparticlesthatcausedspontaneousbreakagewerefoundinallofthesix“butterfly”piecesthatwerecollectedfromdifferentsituations.Thediametersoftheimpureparticleswereintherangeofabout0.3—0.4mm.Allparticleswereregardedassulfideparticlesatthebeginning.Atypicalfracturesectionofthespontaneousbreakage,ascausedbytheimpureparticles,isshowninFig.2.Figure2showsthesphericalparticlesinthetensilelayerandthetrailforthefirstandsecondcracksinthecross-section.Obviously,highlytensilestressesaroundtheimpureparticlesshouldberesponsibleforthefracture.Sixcollectedimpureparticleswereanalyzedbyascanningelectronmicroscope(SEM)equippedwithanenergydispersivespectroscopic(EDS)systemtounderstandthemorphologyandparticlecomponents.Itisinterestingthatwhilefiveparticleswereshowntobethemonolithicsiliconparticlescombinedwithalittleironandtitanium,onlyoneoftheparticleswasasulfideparticle.Theresultsindicatethatoneoftheimportantcausesforspontaneousbreakageintemperedglassisthemonolithicsiliconparticles,inadditiontothenickelsulfideparticlesthatarecommonlyrecognized.Linescanningforcomponentanalysisofthesiliconparticle(seeFig.3)showsverylittleironandtitaniumintheparticle.2stesisstrsAsshowninFig.2,mostofthemonolithicsiliconparticlesaresphericalinshapeandhavesmoothsurfaces.Thehardnessofthesiliconparticleswasmeasuredtobe6.5GPa,whichishigherthanthatoftheglassmatrix(5.4GPa).Theexpansioncoefficientofthemonolithicsiliconparticlesisabout3×10–6/Kto5×10–6/K,andthecoefficientofthecommonglassisdoublethatofthesiliconparticles.Becauseofthemismatchintheexpansioncoefficientsbetweenthematrixandtheparticles,thermalresidualstressaroundtheparticleisinducedastheheat-treatedglasscoolstoroomtemperature.Ontheotherhand,thesameradialstressesincompression,andtangentstressesintension,areaccruedintheglassnearthemonolithicsiliconparticles.Fortheheat-treatedglassthereisacompressivestressinthesurfacelayer,andtensilestressesinthemiddlezonebetweentwoofthesurfacelayers.Thesuperpositionofthetangenttensilestresscausedbythesiliconparticles,andthetensilestressesexistinginthemiddlelayermayleadtoglassfailureifthemaximumstressexceedsacriticalvalue(dependingonthestrengthoftheglass).Thestressconcentrations,forwhichthepeakstressisonlyalittlelowerthanthestrengthoftheglass,constitutesanunsteadysystem,andspontaneousbreakageoccurswhenarandomthermalormechanicalloadisapplied.Thestressesaroundthesiliconparticlesaresphericallysymmetrical,andtheydegradewithanincreaseintheradialdistance.Thefailureisalwaysinitiatesfromtheboundaryofthesmallballduetothelocalstressconcentration,asshowninFig.4.Theradialstressistwotimesstrongerthanthatofthetangentstress.Thefollowingformulasaretakenfromelasticmechanicsforaparticlewithradiusofainthematrix:whereσrisradialstress,σtistangentstress,risthedistancetothecenterpointofthespheresymmetry,andPisthepressureonthesurfaceofthesiliconparticles.wherethesubscriptspandmrefertotheparticleandmatrix,respectively,andEm,aandvaretheelasticmodulus,expansioncoefficientandPoisson’sratio,respectively.Theequationsindicatethat,whenthevalueofeither?Tor(αm–αp)isnegative,ahydrostaticcompressionwilloccurintheparticles;otherwise,ahydrostatictensionwillappear.Since?Tisgivenasaminusintheglassprocess,thetangentstressistensile,andthusthecrackinitiationandextensiononawholeglasssampleisimputedtothetensiletangentstressintheglassnearthesiliconparticle.Themechanismofthespontaneousbreakageresultingfromthesiliconparticleswasanalyzedbyusingthefiniteelementmethod,inwhich40000elementswereused,andthetemperaturedifferencewasshowntobe600℃.Theelasticmoduliofthesiliconparticlesandtheglasswere110GPaand70GPa,respectively.Figure5ashowsthedistributionoftangentstressaroundthesiliconparticle.Thethicknessofthestresszoneincreaseswiththeincreaseinthedimensionsofthesiliconparticles,asshowninFig.5b.Thepeakvalueofthestressisindependentofthedimensionsofthesiliconparticle,accordingtothetheoreticequation.Itisworthnotingthatacrackwillnotoccurwhenthesiliconparticleistiny,evenifthepeakstressishigherthanthestrength.Thisisbecausecrackinitiationinabrittlematerialdependsontheaveragestressintheprocesszonecorrelativewiththepropertiesofthematerial,basedonthemean-strengthcriterion.Fromthispoint,thecriticalsizeoftheimpureparticleshouldbedetermined.Themechanismofspontaneousbreakagecausedbysiliconparticlesseemstonotbethesameintheglasscontainingnickelsulfideparticles.Therefore,atemperedglasscontainingsiliconparticlesmaynotbeendestroyedinthetraditional“heatsoak”process.Theriskofspontaneousbreakageinheat-treatedglasscausedbysiliconparticlesmightincreasewithdecreasingtemperature,becausethelocalstressneartheparticledependsonthetemperaturedifference.3itionellybeenrecoagityforar.2,3,4,4,4,4,4,4,4,4,4,4,4,4.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.4mehn-lacks.3.3.3.3.3.3.3.3.3.3.3.3.3.3.4和3.4.3.4.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.4和3.4.3indexh-12,3.4.3.4和3.4.3.4.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.3.(1)Ithasbeendiscoveredthatoneoftheimportantcausesf