学科分类
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500 个结果
  • 简介:磨擦促使处理(FSP)作为在12修理裂缝的一个方法被调查?公里厚304L不锈钢板。愈合的可行性被用一个PCBN/W-Re工具处理一个逐渐变细的裂缝与表明一25?公里直径肩膀和6.4的大头针长度?公里。实验证明愈合是可能的开始的一个裂缝狭窄然后日益增多地长大到2的宽度?公里。板实验上的祷告被用来为创造发现最好的参数一巩固与贱金属相比与坚硬差别的最少的数量搅动地区。在一些标本的谷物精炼更高导致了大部分搅动地区坚硬,与贱金属相比。谷物尺寸对microhardness的一个阴谋显示出在谷物尺寸和坚硬之间的很强壮的反的关联,从Hall-Petch关系期望。腐蚀测试被执行以便在stir地区的潜在的促进感受性上评估FSP的效果。在1000以后?在在没有腐蚀产品在基础材料控制上或在任何磨擦上形成了,这被发现的房间温度的3.5%盐溶液的断断续续的沉浸的h搅动处理标本。

  • 标签: 不锈钢板 304L 裂缝 磨擦 修理 腐蚀测试
  • 简介:比较了304L不锈钢粉末在不同压力下温压成形与冷压成形的生坯密度和生坯强度,并研究了烧结温度对304L粉末烧结性能的影响。试验结果表明,304L不锈钢粉末的温压生坯密度和生坯强度都高于冷压生坯密度和强度。在800MPa的压制压力下,304L的温压生坯密度为7.07g.cm-3,比冷压提高了0.24g.cm-3,生坯强度为35.6MPa,比冷压提高了22.8%。在1300℃温度下真空烧结后,304L不锈钢粉末压坯的密度为7.50g.cm-3,抗拉强度为471MPa,延伸率为47.7%,硬度为65HRB。

  • 标签: 粉末冶金 温压 烧结 不锈钢粉末
  • 简介:Achievingnotonlyhighmechanicalstrengthsbutalsohighductilityisrecentlyestablishedusinganadditivemanufacturingtechniquecalledselectivelasermelting.Inthepresentstudy,stainlesssteel304Lfullydensesamplesweresuccessfullyprintedusingthe3Dsystems-ProX300printingmachine.TheductilityandtensileyieldstrengthwerealmosttwoandthreetimeshighercomparedtothoseofASTMcast'salloy.Honeycomblikenano-cellularstructurew让hdifferentorientationwasobservedinthefinegrains(-4μm)duetofastcoolingrate.Inadd让ion,theformationofmartensitephaseinrandomgrainsisalsoacontributortothestrengths.Furthermore,negativeresidualstressesinthebuildandhorizonraldirectionsweredetectedandassistedfurtherincreaseinthetensilestrength.Fractographyrevealedtheductilefeatureofplasticdeformationandthecrackopeningsatunmeltedparticlesorpores.

  • 标签: ADDITIVE manufacturing STAINLESS steel Powder SELECTIVE
  • 简介:Twothermo-mechanicalcontrolledprocesses(TMCP)includingcontrolledrollingandacceleratedcoolingareproposedfortheproductionofheavygaugeSUS304Lausteniticstainlesssteelplateswithdifferentstrengthsandothercharacteristics.BasedontherecrystallizationmechanismandcarbideprecipitationbehaviorofSUS304Lausteniticstainlesssteel,TMCPprovidesapowerfulmeanstocontrolthemicrostructureandprecipitationofthehotrolledsteelplatebythecontrolledrollingandacceleratedcoolingprocess.Thedislocationdensityandgrainsizearethemainfactorsindeterminingthestrengthofthestainlesssteelplates.Therefore,itisnecessarytostrictlycontrolthehotrollingparameters,includingparameterssuchasthefinishhotrollingtemperatureintherecrystallizationtemperatureregionandthetotalreductioninthenon-recrystallizationregion.Furthermore,inordertoavoidcarbideprecipitationandguaranteetheintergranularcorrosionresistanceofTMCPSUS304Lausteniticstainlesssteel,acriticalcoolingrateafterrollingisdetermined.

  • 标签: 奥氏体不锈钢 不锈钢板 控轧控冷 TMCP工艺 制造 技术
  • 简介:摘要:本文主要介绍了台山核电站一期工程2#机组常规岛项目高压给水系统材质为TP304L的大口径厚壁不锈钢管道在安装过程中,通过一系列严格的焊接工艺措施和焊接操作技巧,有效地保证了管道安装焊接质量,对今后类似大口径厚壁不锈钢管道的焊接可提供良好的借鉴作用。

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  • 简介:Inthisstudy,resistancespotweldabilityof180gradebakehardeningsteel(BH180),7123gradeinterstitialfreesteel(IF7123)and304gradeausteniticstainlesssteel(AISI304L)witheachotherwasinvestigated.Inthejoiningprocess,electrodepressureandweldcurrentwerekeptconstantandsixdifferentweldtimewerechosen.Microstructure,microhardness,tensile-shearpropertiesandfracturetypesofresistancespotweldedjointswereexamined.Inordertocharacterizethemetallurgicalstructureoftheweldedjoint,themicrostructuralprofilewasdeveloped,andtherelationshipbetweenmechanicalpropertiesandmicrostructurewasdetermined.Thechangeofweldtime,nuggetdiameter,theHAZ(heataffectedzone)widthandtheelectrodeimmersiondepthwerealsoinvestigated.WeldedjointswereexaminedbySEM(scanningelectronmicroscopy)imagesoffracturesurface.Asaresultoftheexperiment,itwasdeterminedthatwithincreasingweldtime,tensileshearloadbearingcapacity(TLBC)increasedwithweldtimeupto25cycleandtwotypesoftearingoccurred.ItwasalsodeterminedthatwhilethefailureoccurredfromIFsideattheBH180+IF7123joint,itoccurredfromtheBH180sideattheBH180+AISI304Ljoint.

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  • 简介:本文通过将SUS304、SUH409L、06Cr13三种不锈钢在35℃,6%FeCl3+HCl的混合溶液中进行点腐蚀试验,将腐蚀后腐蚀速率、宏观特征、微观组织特征、形貌特征等进行了阐述及对比,并根据化学成分、微观组织结构、腐蚀后的形貌特征等进行了腐蚀原因分析。

  • 标签: 腐蚀速率 点蚀 FECL3
  • 简介:目的:探讨严重多发伤病人的急救与治疗。方法:回顾分析了我院1993年12月-2009年3月收治304例严重多发伤病人的救治经过、方法及结果。结果:304例中287例治愈出院,17例死亡,治愈率94.4%。结论:规范的早期急救,补充血容量防治休克,正确诊断,及时手术治疗,积极防治并发症是提高救治成功率的关键。

  • 标签: 严重多发 救治
  • 简介:Non-metallicinclusionisthemainreasonforthepresenceofsurfacedefectsincold-rolledsteelstrip.Inthisstudy,thecomposition,morphology,andsizeofthenon-metallicinclusioninhot-rolled304stainlesssteelstripsareanalyzed.Cold-rolled304stainlesssteelstripswithdifferentcold-rollingreductionhavebeenprepared,andthemorphologyandsizeofinclusioninthesecold-rolledstripsarealsoanalyzed.Furthermore,thedeformationbehaviorofanon-metallicinclusionduringthecold-rollingprocessisstudied.TheresultsshowthatCaO-SiO2-MgO-Al2O3,akindofbrittlecompoundoxide,isthemaintypeofinclusioninhot-rolled304stainlesssteelstrips.Duringthecold-rollingprocess,ductiledeformationofthistypeofinclusionisnotobvious,wherelargeinclusionsarecrushed,andtheaveragesizeofinclusionsincold-rolledstripsdecreasedwhilethecold-rollingreductionincreased.

  • 标签: 非金属夹杂物 304不锈钢 变形行为 冷轧带钢 带钢表面缺陷 冷轧钢带
  • 简介:摘要不锈钢软管产品易开裂是实际生产中普遍存在的技术难题。本文对某安装后不久的304奥氏体不锈钢波纹软管失效的原因进行分析,通过采用先进的仪器进行宏观检验,化学成分分析,金相检验,断口分析,能谱分析,最后综合总结得出软管失效的原因。希望能为有关方面的需要提供帮助。

  • 标签: 304奥氏体不锈钢 理化检验 失效分析
  • 简介:GlowdischargeplasmanitridingofAISI304austeniticstainlesssteelhasbeencar-riedoutfordifferentprocessingtimeunderoptimumdischargeconditionsestablishedbyspectro-scopicanalysis.ThetreatedsampleswereanalysedbyX-raydiffraction(XRD)toexplorethechangesinducedinthecrystallographicstructure.TheXRDpatternconfirmedtheformationofanexpandedaustenitephase(γN)owingtoincorporationofnitrogenasaninterstitialsolidsolu-tionintheironlattice.AVickersmicrohardnesstesterwasusedtoevaluatethesurfacehardnessasafunctionofindentationdepth(μm).Theresultsshowedclearevidenceofsurfacechangeswithsubstantialincreaseinsurfacehardness.

  • 标签: 光学诊断学 等离子体渗氮 奥氏体不锈钢 光热放电等离子体
  • 简介:Objective:Toobservetheeffectsofthermalstressonproliferationofhumanvascularendothelialcells(VECs)andexploreitssignificance.Methods:ChangesofVECsproliferationwereinvestigatedwith3H-TdRincorporationmethodafterECV304wastreatedat43℃for2hours,whileexpressionsofintercellularadhesionmolecule-1(ICAM-1),inhibitorofdifferentiation-1(ID1),andP16andP21proteinsweredeterminedbyWesternBlotting.Results:TheeffectofinhibitionofVECsgrowthafterthermalstresswasdetectedby3H-TdRincorporationexperiment.WesternblottingshowedICAM-1,amarkerofactivatedendothelialcells,wasincreasedmarkedlyafterthermalstress.ExpressionofID1proteindeclinedgraduallywithincreasingexpressionsofitsdownstreamgenes,P16andP21followingthethermalstress.Conclusions:ThermalstresscouldstronglyactivateVECsandinhibitproliferationofVECsthroughID1,thusdownregulatingcyclin-dependentkinaseinhibitors,P16andP21,whichmightbeanessentialpathwayforrecoveryofVECsafterthermalstress.

  • 标签: 热应激 ECV304细胞增殖 抑制作用 血管内皮 P16 P21
  • 简介:通过对304不锈钢生产工艺研究,解决了304不锈钢冷轧板抛光性能差的问题。抛光时间由原来的40~90min缩短至15~20min,抛光后成品粗糙度降低至0.02~0.045μm,使304不锈钢冷轧板抛光性能得到改善,抛光效率得以提高。

  • 标签: 304不锈钢 冷轧 抛光 工艺控制
  • 简介:无论从哪个角度来看.奥特蓝星UHP304耳机的做工都足以给您留下深刻的第一印象。简洁、纤细的外观设计.令它躺在包装盒里也显得与众不同。UHP304耳机以两根韧性很强的钢条作为固定头戴.其压力比较适中.长时间使用也不会感觉不适。它的两个耳筒外壳采用硬塑胶成形,外观颜色与整体的设计风格搭配得很协调.内里采用海绵加软塑布包裹.

  • 标签: ALTEC 耳机 外观设计 设计风格 外观颜色 包装盒
  • 简介:心电检查对心血管疾病是一种无创伤可重复性必不可少的1项检查,现已普及到基层保健站,社区卫生服务中心,已成为血尿粪3大常规外又1个常规检查。兹将我院1998年至1999年10月期间住院老年病人304例首次心电图检查结果,分析如下。1临床资料304例年龄均在60岁以上,其中60~90岁44例(男29、女15),70~79岁143例(男82、女61),80~89岁106例

  • 标签: 老年人 住院病人 心电图 异常
  • 简介:辣椒雄性不育系304A是陕西省宝鸡市农业技术推广服务中心利用不育源0918A与二荆条测交,继续回交4代培育而成,2016年通过省级审定登记。该不育系平均株高66cm,株幅60cm,始花节位9~10节。用保持系304B授粉,果实线形,青果深绿色,成熟后呈深红色,平均果纵径20cm,果横径1.4cm,味辣,品质较好,耐病毒病和疫病,综合抗性较强。

  • 标签: 雄性不育 选育 304A
  • 简介:The304stainlesssteelstripsweredepositedonelayeroncarbonsteelbasemetalbyelectroslagstripcladding(ESC)andsubmergedarccladding(SAC),respectively.ThesolidificationmicrostructureofESCmetalwasanalyzedbytheopticalmicroscopy,scanningelectronmicroscopeandenergydispersivespectroscopy.Thecorrosionresistancestudiesofstripcladdingmetalswerecarriedoutin10%oxalicacidelectrolyticetchingtest.TheresultsshowedthatthecladdingmetalobtainedbyESCpresentedlowcontentofC,highcontentofCrandenoughalloyingelementofNiinthechemicalcomposition.ThetransitionzoneofESCwithsmallwidthwasalmostparallelwiththebasemetal,leadingtoalowerdilution.Therearethreetypesofsolidificationmodes(A→AF→FA)occurredintheESCmetalduetothedecreaseofcoolingrateanddegreeofdilutionfromthetransitionzonetothetopofESCmetal.Asaresult,themicrostructureofESCmetalexhibitedmainlyaustenitewithasmallamountofferrite,contributingtoachievementofbettercorrosionresistance.

  • 标签: 带极电渣堆焊 耐腐蚀性能 显微组织 304不锈钢 扫描电子显微镜 熔敷金属