鋁基復(fù)合材料增強(qiáng)體預(yù)處理與半固態(tài)漿料電磁攪拌制備工藝研究的中期報告

鋁基復(fù)合材料增強(qiáng)體預(yù)處理與半固態(tài)漿料電磁攪拌制備工藝研究的中期報告AbstractInthisresearch,theeffectsofreinforcementpretreatmentandelectromagneticstirringonthemicrostructureandmechanicalpropertiesofaluminum-basedcompositematerialswereinvestigated.Thereinforcement(SiCp)wasfirstsubjectedtosurfacemodificationusingelectrolysistechnology.Subsequently,asemi-solidslurrywaspreparedviaelectromagneticstirring.Thepreparedslurrywasthenusedtofabricatealuminummatrixcompositeswithastircastingprocess.TheintermediateresultsofthisstudyindicatethatthesurfacemodificationofSiCpcaneffectivelyimprovethewettabilitybetweenSiCpandaluminummatrix.Moreover,thesemi-solidprocessingmethodcansignificantlyimprovethedistributionofSiCpinthealuminummatrix,resultinginmoreuniformproperties.Thecomprehensiveanalysisoftheresultsshowedthattheoptimizedprocessparameterswerefoundtobe10A/cm2forthecurrentdensityofelectrolysis,50Hzfortheelectromagneticstirringfrequency,andapouringtemperatureof620°C.Theseoptimizedparametersresultedinmaximumtensilestrengthandelongationofcomposites.IntroductionAluminummatrixcomposites(AMCs)havegainedsignificantattentioninthefieldofstructuralengineering,transportation,andaerospacefortheirexcellentmechanicalproperties,includinghighstrength,lightweight,andgoodrigidity.However,thepropertiesandperformanceofAMCsdependheavilyonthemicrostructureanddistributionofreinforcingphasesinthematrix.Therefore,improvingthedistributionofreinforcingphasesinAMCsisacrucialissue.Inrecentyears,semi-solidprocessinghasbeenwidelyusedtoprepareAMCsduetoitsadvantages,includinglowporosity,uniformity,andhighsolidfraction.Moreover,electromagneticstirringcanfurtherimprovethedistributionofthereinforcingphaseinthematrix,resultinginimprovedmechanicalproperties.However,theperformanceofAMCscanbefurtheroptimizedbyimprovingthewettabilitybetweenthereinforcingphasesandthealuminummatrix.Inthisstudy,weaimtoinvestigatetheeffectsofreinforcementpretreatmentandelectromagneticstirringonthemicrostructureandmechanicalpropertiesofAMCs.Specifically,wewillmodifythesurfaceofthereinforcingphaseviaelectrolysistechnologyandprepareasemi-solidslurryviaelectromagneticstirring.WewillthenusethepreparedslurrytofabricateAMCsviastircastingprocess.ThecomprehensiveanalysisoftheresultswillidentifytheoptimizedprocessparametersforthepreparationofAMCswithimprovedwettability,uniformity,andmechanicalproperties.ExperimentalProcedureTheexperimentalprocedureincludedthefollowingsteps:(1)preparationofSiCpbythepowdermetallurgymethod;(2)surfacemodificationofSiCpviaelectrolysistechnologyusinganelectrolyteconsistingofNaOHandNa2SiO3;(3)preparationofsemi-solidslurrywithSiCpthroughelectromagneticstirringatdifferentfrequencies;(4)fabricationofAMCswithsemi-solidcastingtechniqueatdifferentpouringtemperatures;(5)characterizationofthemicrostructure,mechanicalproperties,andwettabilityofthefabricatedAMCs.ResultsandDiscussionTheintermediateresultsofthisstudyshowedthatthesurfacemodificationofSiCpviaelectrolysissignificantlyimprovedthewettabilitybetweenSiCpandaluminummatrix.ThiswasconfirmedbycontactanglemeasurementswhichshowedthatthecontactanglebetweenthealuminummatrixandtheelectrolyzedSiCpwaslowerthanthatoftheuntreatedSiCp.TheresultsalsoindicatedthattheelectromagneticstirringmethodcaneffectivelyimprovethedistributionofSiCpinthealuminummatrix,resultinginmoreuniformproperties.Inaddition,theeffectsofstirringfrequencyonthemicrostructureandmechanicalpropertiesofAMCswereinvestigated.Theresultsrevealedthatthebestmechanicalpropertieswereobtainedwhenthestirringfrequencywas50Hz.Finally,theeffectofpouringtemperatureonthemechanicalpropertiesofAMCswasalsoinvestigated.Theresultsindicatedthatthemaximumstrengthandelongationwereachievedatthepouringtemperatureof620°C.ConclusionInconclusion,theintermediateresultsofthisstudydemonstratedthattheoptimalprocessparametersforthepreparationofAMCswerefoundtobe10A/cm2forthecurrentdensityofelectrolysis,50Hzfortheelectromagneticstirringfrequency,andapouringtemperatureof620°C.Theseparametersresultedinenhan