简介:Aninvestigationonthedischargecharacteristicofadielectricbarrierdischarge(DBD)devicewascarriedoutusingbareandZnO-coatedaluminadielectriclayerinatmosphericpressureair.HighlyconductiveZnOfilmwasfirstdepositedonthealuminasurface,andthecharacteristicsofthedielectricbarrierdischargewereexaminedandcompared.ExperimentalresultshowsthatdischargebehaviorwasdefinitelyimprovedinthecaseofZnO-coateddielectricbarrierdischarge.Relevantexplanationisofferedtodescribeitsdischargephysics.
简介:Electricalpropertyofamicro-plasmaspraysystemwithdifferentworking-gasfeedingschemeswastestedtooptimizetheplasmasprayprocess.Thearcvoltagewithanintegratedgasinjectionmodeishigherthanthatwithradialinjectionoraxialinjectionmodes.Thus,anintegratedgasinjectionmodewithanexcellentelectricalcharacteristicwasadoptedtodepositalumina-titaniacoating.Themicrostructure,bondingstrengthandhardnessoftheplasmasprayedalumina-titaniacoating,asafunctionofthesprayingparameters,e.g.,plasmacurrent,gasflowrateandgaspressure,werestudied.Itwasshownthatthesprayingparametersaffectedremarkablyontheinicrostructureofthecoating.Differenttendenciesinbondingstrengthandhardnesswerealsoshownfordifferentsprayingparameters.Atanarccurrentof250A,agasflowrateof20L/rninandagaspressureof0.5MPa,thebondingstrengthandmicro-hardnessofthecoatingsreach40.6MPaandHV1406.1,respectively.