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چکیده
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The aimofthisstudyisthesynthesisofaluminum-basedmetalmatrixnanocompositesreinforcedwith in situTiCandAl2O3 hybridreinforcementsbythemechanicallyactivatedcombustionsynthesis.The composites werefabricatedfromthepowderblendsconsistingofaluminum,rutileandgraphitewithan excessamountofaluminumfollowingthe14Al–3TiO23C systemandmilledupto30h.Phaseevolu- tions andstructuralchangesduringballmillingandcombustionsynthesiswerestudiedbyX-raydif- fraction technique, field-emission gunscanningelectronmicroscopyandtransmissionelectronmicro- scopy.Theresultsshowedthatevenafter10hofmilling,nonewphaseswereformed.Theincreasingof milling timecausedthebroadeningofallthepeaksindicatingadecreaseinthecrystallitesizeandan increase inthelatticestrain.TheseresultsshowedthatAl,CandTiO2 nanocrystallitescouldbeobtained during theball-millingprocess.Theresultofcombustionsynthesisofun-milledpowdersconfirmed that no newphaseswerefound.Incomparisonwithun-milledpowdermixture,the10hmilledpowdercould be easilyignitedandXRD,HRSEMandTEMresultsconfirmed thatAl/TiC–Al2O3 nanocomposite was successfully synthesizedthroughcombustionmethodfromthemechanicalactivatedpowdermixture. Mechanical activationviahighenergyball-millingprovidedtotheinitialpowdermixtureextraenergy, which isneededtoincreasethereactivityofpowdermixtureandtomakepossibletheignitionandthe sustaining ofcombustion.
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