简介：Ionimplantationisapowerfulmethodforfabricatingnanoparticlesindielectric.Fortheactualapplicationofnanoparticlecomposites,acarefulcontrolofnanoparticleshastobeachieved.Inthisletter,thesize,distributionandmorphologyofAgnanoparticlesarecontrolledbycontrollingtheioncurrentdensity,ionimplantationsequenceandionirradiationdose.SinglelayerAgnanoparticlesareformedbyAg+ionimplantationatcurrentdensityof2.5μA/cm2.ByAgandCuionssequentialimplantation,thesizeofsinglelayerAgnanoparticlesincreases.While,byCuandAgionssequentialimplantation,uniformAgnanoparticleswithwidedistributionareformed.ThemorphologyofAgnanoparticleschangestohollowandsandwichednanoparticlesbyCu+ionirradiationtodosesof3×1016and5×1016ions/cm2.TheopticalabsorptionpropertiesofAgnanoparticlesarealsotailoredbytheseways.

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简介：Themartensitic/ferriticsteelshavebeenusedasboilerandturbinematerialsinpowerplants,andalsobeenselectedaspotentialmaterialsforstructuralmaterialsinnuclearreactors.Inthispaper,thekineticanalysisofthemartensiteformationandmicrostructuralcontrolofhigh-Crmartensitic/ferriticsteelsarereviewed.Amodularapproach,incorporatingFisherpartitioningnucleationandanisotropicgrowthforimpingement,wasproposedtodescribethemartensiteformationkineticsunderdifferentcoolingrates.Thekineticanalysissuggestedathermal-activatedgrowthfeatureoccurringduringthemartensitictransformationofmartensiticsteels.Themicrostructurecanbetunedbycompositionoptimizationandvariouscombinationsofheattreatmentparameters(temperature,time,severeandminordeformation).Fortheapplicationinpowerplant,thepotentialofboundary-design,refinementoforiginalaustenitegrainsizeandthefinalmartensiticlath,pinningeffectofstablecarbides,inimprovingtheperformancesofmartensitic/ferriticsteelsatelevatedtemperaturesshouldbeinvestigatedmorethoroughly.Furthermore,effortsshouldbemadetoexploretheeffectsofretainedausteniteontheimprovementofhigh-temperaturecreepstrength.Fortheapplicationofnuclearplants,attemptsshouldalsobemadetoproduceFepowderswithuniformlydistributedoxideparticlesbychemicalreactions.