简介:ForimprovingthepropertiesofSiC-mullitecompositeceramicsusedforsolarsensiblethermalstorage,MnO_2wasintroducedassinteringadditivewhenpreparing.ThecompositeceramicsweresynthesizedbyusingSiC,andalusite,α-Al_2O_3asthestartingmaterialswithnon-contactgraphite-buriedsinteringmethod.PhasecompositionandmicrostructureofthecompositeswereinvestigatedbyXRDandSEM,andtheeffectofMnO_2onthepropertiesofSiCcompositeswasstudied.ResultsindicatedthatsamplesSM1with0.2wt%MnO_2additionachievedtheoptimumproperties:bendingstrengthof70.96MPa,heatcapacityof1.02J·(g·K)-1,thermalconductivityof9.05W·(m·K)-1.ProperadditionofMnO_2wasfoundtoweakenthevolumeeffectofthecompositesandimprovethethermalshockresistancewithanincreasedrateof27.84%forbendingstrengthafter30cyclesofthermalshock(aircoolingfrom1100℃toRT).