堿金屬鈮鉭銻酸鹽無鉛壓電陶瓷的制備和性能表征.pdf

1、合肥工業(yè)大學碩士學位論文堿金屬鈮鉭銻酸鹽無鉛壓電陶瓷的制備和性能表征姓名：方旭升申請學位級別：碩士專業(yè)：材料學指導教師：左如忠20090301ThePreparationandPerformanceCharacterizationof(Sb，Ta，Li)ModifiedAlkaliMetal—ContainingNiobate—BasedPiezoceramicsABSTRACTTheSb，TaandLimodifiedsodium—p

2、otassiumniobatesystemhasbeenaresearchfocusinthelead—freepiezoelectricceramicsfieldnowadaysBecausetheelectronegativityofSbishigherthanthatofNb，itcanstrengthenthecovalencyofthesystem，improvethepiezoelectricperformances，and

3、thustheamountofSbisfixedatahighvalueinthisthesis(6m01％)ConsideringthatvolatilizationofNaismoreseriousthanthatofKinthesinteringprocess，theamountofNaisusedslightlymorethanthatofKOnthebasisofthiscomposition，(Na052K048)(Nbo9

4、6Sb004)03，LiandTainequalmolarratioareaddedtoformanmorphotropicphaseboundary(MPB)inthehopeofimprovedperformances：Then，thesinteringprocessisoptimized，andtheinfluenceofCuO—dopingontheperformancesisinvestigatedCompleteandhom

5、ogeneoussolidsolutionscanformbetweenLi，Ta，Sb十ionsandsodiumpotassiumniobatewithinthestudiedscopeTheadditionoflithiumtantalate(TL)improvesthesinteringperformances，whiletheparticlesizedistributionisnotuniformWithincreasingt

6、heamountofTL，thephasestructureatroomtemperatureischangedfromanorthorhombicphasetoatetragonalphasesuchthatanMPBiSformedwithin0035x004TheCurietemperature(Tc)increaseswithincreasingtheamountofLTandthephasetransitiontemperat

7、urebetweenorthorhombicphaseandtetragonalphase(Tot)movestoomtemperaturesuchthattheperformancesareimprovedExcellentperformancesarepresentinthecompositionwithx=004，d33=335pC／N，kp=53％，6；3=2063，Qm=41，Te=291℃，showingthepotenti

8、alforpracticalapplicationTheresultshowsthattheperformancescanbeimprovedinthewaythatthemoreamountofSbisaddedandthecomponentisdesignedneartheMPBItisfoundthattheinfluenceofthesinteringprocessontheperformancesisgreatThelower

9、sinteringtemperature，theshortersoakingtimeandNaexcessesintheinitialcompositiontendtocauseabnormalgraingrowthWithincreasingsinteringtemperatureandsoakingtime，thegraingrowsbetter，andthedensityincreasesandreachesitsmaximuma