简介:PrecipitationstudywascarriedoutinNi-35at.pctCralloybymeasuringelectricalresistivityatdifferentageingtemperaturesandlongageingtimes.Duringageing,itwasobservedthatelectricalresistivityinitiallyrosewithageingtimeandthenfellafterverylongageingataconstanttemperature.TheinitialincreaseinresistivityduringageingmaybeattributedtotheformationofGPzones/Cr-richprecipitatesatearlystagesbynucleationprocessanddecreaseinresistivity,andafterattainingamaximum,isduetothegrowthofprecipitateparticlesandsubsequentlybycoarseningoftheseprecipitates.TheresultsofelectricalresistivitymeasurementsduringageingwereconfirmedbyX-raydiffractionanalysisindicatingtheformationofaCr-richphaseandaCr3Ni2phaseintheNimatrix.
简介:1.IntroductionLightrareearthadditioncanremarkablyenhancetheservicelifeofFe-Cr-Alalloyforelectricalheatingelement,butitscontentinthealloymustbecontrolledbelowthelevelof0.1wt-%.Whenthecontentexceedsthat,theperformance
简介:Themicrostructuralevolutionsofadvanced9-12%Crferrite/martensiteheat-resistantsteelsusedforpowergenerationplantsarereviewedinthisarticle.Despiteofthesmalldifferencesinchemicalcompositions,thesteelssharethesamemicrostructureoftheas-temperedmartensite.Itisthethermalstabilityoftheinitialmicrostructurethatmattersthecreepbehavioroftheseheat-resistantsteels.Themicrostructuralevolutionsinvolvedin9-12%Crferriteheat-resistantsteelsareelabo-rated,including(1)martensiticlathwidening,(2)disappearanceofprioraustenitegrainboundary,(3)emergenceofsubgrains,(4)coarseningofprecipitates,and(5)formationofnewprecipitates,suchasLaves-phaseandZ-phase.Theformerthreemicrostructuralevolutionscouldberetardedbyproperlydisposingthelattertwo.Namelyimprovingthestabilityofprecipitatesandoptimizingtheirsizedistributioncaneffectivelyexertthebeneficialinfluenceofprecipitatesonmicrostructures.Inthissense,themicrostructuralstabilityofthetemperedmartensiteisinfactthestabilityofprecipitatesduringthecreep.Manyattemptshavebeencarriedouttoimprovethemicrostructuralstabilityof9-12%Crsteelsandseveralpromisingheat-resistantsteelshavebeendeveloped.
简介:粉末催化剂Cu-Cr-O用于碳nanotubes(CNT)的合成的一篇小说被开发,它经由氨降水方法被准备。扫描热量计(TG-DSC)的thermo-gravimetric/differential的技术,X光检查衍射(XRD)以及扫描电子显微镜学(SEM)和传播电子显微镜学(TEM)被采用了分别地描绘热分解过程,晶体阶段和同样综合的材料的微结构的形态学。当先锋在400,500,600,和700琠慨?桴獩洠瑥潨?獩猠極慴汢?潦?牰摥捩楴杮琠敨猠牴湥瑧?景挠浯潰楳整氠浡湩瑡獥?桴?業牣浯'炭暘e牴湥瑧?桴潥祲椠?慲歮摥戠?潣灭牡湩?瑩眠瑩?污?桴?被锻烧时,结果证明碳nanotubes成功地作为催化剂用Cu-Cr-O被综合業牣?敬敶?湡?桴?敢瑳琠潷洠捡潲氭癥汥琠敨牯敩?档獯湥映潲?桴?潗汲?楗敤?楡畬敲?數'元沞
简介:弧与cored电线喷洒被使用在低碳钢底层上扔FeMnCr/Cr3C2涂层,也就是FM1,FM2和FM3。涂层的热吃惊电阻被调查在热吃惊抵抗上估计Cr3C2内容的影响。在热骑车测试下面的涂层的特征被光显微镜学,地排放扫描电子显微镜(FE-SEM)和精力分散光谱(版本)学习,X光检查衍射(XRD)。试验性的结果证明涂层的坚硬增加,结合力量随涂层的Cr3C2内容的增加稍微减少。作为结果,FM2涂层拥有最好的热吃惊抵抗,归因于它比那些的更好热的扩大火柴和FM3涂层的wettability,更少的氧化物率比FM1涂层在涂层从裂缝形成和繁殖制止的。
简介:微单VⅠ是面向年轻人的一款极致完美、智能操控、张扬个性、便于存放的绿色交通工具,希望能解决城市年轻人出行的痛点,在城市里年轻人希望拥有一款轻便方便折叠又不占空间的代步工具。更加符合人体工程学的车架角度设计,专为长时间骑行而改进的舒适转把,更加符合电动车刹车力矩的刹把,简单快捷的折叠结构,高度整合的电池托架结构,以及为夜间安全出行缜密设计的灯光系统,
简介:Toobtainthecompatiblematerialofhighhardnessandhightoughness,Hadfieldsteelmatrixcomposites,reinforcedbyhigh-Crcastironbarsmadeofflux-coredweldingwires,whichwereinsertedintotheHadfieldsteelmelt,wereinvestigated.Themechanicalpropertiesofthreematerials,ie,compositesforas-castandquenching-watercondition,aswellasHadfieldsteel,werecompared.Theresultsshowthatthealloypowderinsideflux-coredweldingwirescanbemeltedbytheheatcapacityofHadfieldsteelmeltandsolidifyintohigh-Crcastironbars.Theimpacttoughnessofthecompositeforquenching-waterconditionishigherthanthatofthecompositeforas-castconditionandislowerthanthatoftheHadfieldsteel,butitcanstillmeettherequirementsofhardnessandtoughnessinindustrialapplication.Regardlessofloadvariation,compositeforquenching-waterconditionshowsbetterwearresistancethanthoseofthecompositeforas-castconditionandHadfieldsteel.ThemodifiedfracturetoughnessandwearresistanceofcompositesareattributedtonotonlythecombiningactionsofHadfieldsteelmatrixandhigh-Crcastironbars,butalsotheeffectofheattreatment.