简介:力量的发展和用在在低温度的硫酸盐环境下面的低水文件夹比率的石灰石粉末做的基于水泥的材料的攻击的形式被学习。结果显示当水文件夹比率比0.40低时,有石灰石粉末的基于水泥的材料在为120d在低温度在10%镁硫酸盐答案被浸泡,并且在在200d岁时被浸泡以后在外观有重要变化以后在外观有不足道的变化。扩大损坏和脱落在不同层次发生在具体测试立方体的表面上。当石灰石粉末占大约28%似水泥的材料时,与水文件夹比率的减少,在材料在200d岁时在低温度在镁硫酸盐答案被浸泡以后,压缩力量损失逐渐地减少了。在有不到0.4的水文件夹比率和石灰石粉末卷的标本以后大与20%在200d岁时在低温度在10%镁硫酸盐答案被浸泡比,带攻击的破坏被引起到具体测试立方体的石膏,没有thaumasite硫酸盐攻击。
简介:过程的热踩,熄灭并且划分的一个新奇设计计划在可抑制的硼钢被进行获得nanometric包括极其细小的保留的奥氏体和马氏体的双微观结构。材料拥有优秀机械性质,这被显示出,没有损害力量,韧性能进一步被改进。最新对待的钢与热印上并且熄灭的钢的相比从6.6%~14.8%显示出优秀机械性质和钢增加的全部的延伸。因此,这种钢成为了另一组先进高张力钢。为如此的优秀机械性质主要负责的微观结构被调查。
简介:为铸造过程(VIMP)的真空注入的一个低粘性环氧基树脂树脂系统(猎人1564/3486)的chemorheological行为与粘性实验被学习。dual-Arrheniusrheological模型和设计粘性模型被建立并且与试验性的数据相比。结果证明在dual-Arrhenius模型计算的更早的阶段的粘性比试验性的数据小,当设计模型计算的数据更大时。一起联合二个模型能以一种更可信的方式预言树脂系统的rheological行为。为VIMP的树脂系统的处理窗口基于二个模型被决定。处理温度的最佳是3045楎倭挠瑡污吗?
简介:TheironrustphasesformedonIowalloysteelscontainingdifferentquantitiesofCrelementhavebeencharacterizedusingEPMA,Ramanspectroscopy,TEM,opticalmicroscopyetc.Theionselectivepropertiesofsynthesizedrustfilmswiththesamephaseconstituentastheatmosphericcorrosionproductswereinvestigatedusingself-madeapparatus.TheresultsshowedthatcorrosionlossofsteelsexposedinmarineatmospheredecreasedrapidlyastheCrcontentofthesteelwasincreased.Cr-containingsteelswerecoveredbyauniformcompactedrustlayercomposedoffineparticleswithanaveragediameterofseveralnanometers.InnerrustlayerofCr-containingsteel(2massfraction)wascomposedofα-CrxFel-xOOH,withCrcontentofabout5massfraction.Suchrustlayershowedcationselectiveproperty,andcoulddepressthepenetrationofCl-tocontactsubstratesteeldirectly.
简介:Onthebasisoftransformationkineticsandthermodynamics,theaustenite-ferritetransformationstarttemperatureduringdeformationwaspredictedforseveralgradesoflow-carbonsteelsunderdifferentprocessingconditions.ResultsindicatethatAr3dtemperaturemostlydependedonalloyingcompositionandprocessingparameters.Ar3dincreasedasstrainrateorstrainincreasedforthesamesteelgrade.Inviewofenhancementofdeformationontransformation,thebasickineticsmodelwasestablishedtosimulatedeformationinducedtransformationbehavior,usingwhichtheinfluenceofthedeformationstoredenergyandeffectivedeformationledgeonthenucleationandgrowthcanbeconsidered.Thesimulatedresultsareingoodagreementwithexperimentresults.
简介:硼(B)的增加经常被采用增加bainitic钢的hardenability。尽管它是众所周知的,那B能延迟bainitic转变动力学,B怎么在ausforming以后影响bainitic转变动力学,仍然不是清楚的。由系统的高分辨率的dilatometry测试,现在的工作表明bainitic转变动力学包括孵化时间,转变速度和转变体积部分从所有方面在ausforming以后与B增加在低C钢被加速。为没有B增加的一样的钢,相反,转变速度和转变体积部分在ausforming以后被延迟。当某硼能与脱臼交往因此提高bainite成核率,ausforming能在优先的奥氏体谷物边界减少B分离,这被建议当某硼能与脱臼交往。而且,auforming能精制bainitic捆的平均体积。基于在成核率和bainitic捆的精炼的增加之间的竞争机制,bainitic转变动力学上的B和ausforming的效果被讨论。
简介:
简介:二种Mn-Si-Mo低碳钢被设计在热卷的低碳bainitic的微观结构和性质上学习Mn的效果钢。到生产花费了的还原剂,0.13%的一个很低的瞬间内容两个都被加在一起钢。在热滚动以后,样品的机械性质被测试。微观结构被光显微镜和传播电子显微镜观察并且分析。结果证明测试的钢的力量随Mn的增加增加内容,当延伸减少时。当Mn内容增加时,bainite微观结构增加。结果能为作文提供一个理论基础设计和低费用的工业生产低碳bainitic钢。
简介:TheexitwavefunctionincludingzeroandhighorderLauezoneshasbeensimulatedbybothmulti-slicemethodandelectrondynamicdiffractionanalyticalexpression.Coincidenceofthesimulationsbythesetwomethodswasachieved.ThecalculatedresultsshowedthattheexitwavefunctionhighlydominatedbyzeroorderLauezone,whilehighorderonesmodifytheexitwavefunctiontosomeextentdependingonthesituation.HighorderLauezoneeffectsbecomeimportantforthefollowingcases:sampleconsistsoflightelements,thethicknessisverythin,latticeplanarspacingperpendiculartothedirectionoftheincidentbeamislarge,andtheelectronbeamhaslongwavelength.InthesecasestheexitwavefunctionshouldbecorrectedbyaddinghighorderLauezoneeffects.TheanalyticalexpressioniseffectiveandconvenientfordealingwithhighorderLauezoneeffects.
简介:氢导致了裂开(HIC)有三不同微观结构,小粒的bainite与板条bainite的高力量管道钢的行为(GB?+?磅),小粒的bainite与针状的铁酸盐(GB?+?AF),并且伪多角形的铁酸盐(QF),被基于标准NACETM0284使用腐蚀实验学习。HIC实验在氢硫化物被进行(H2S)浸透的答案。试验性的结果证明有GB的钢?+?AF和QF微观结构介绍优秀腐蚀抵抗给HIC,而在磅的bainite板条和马氏体/奥氏体的阶段?+?GB微观结构为差的腐蚀抵抗负责。与铁酸盐阶段相比,bainite微观结构展出更高的力量和HIC的裂缝危险性。AF?+?GB微观结构被相信在设计的钢之中有机械性质和电阻的最好的联合到HIC。
简介:低扩大的superalloys是易受影响的焊接团结裂缝和影响热的地区(HAZ)microfissures。预言团结裂开,Qbasic语言过程被开发,最容易溶解的产品的团结反应顺序,类型,和数量是计算的。被L(+NbC)和L(+洗)作为表明的、主要团结跟随最容易溶解的反应顺序为GH903和GH907;因此,终端最容易溶解的成分由/NbC和/Laves组成。当时为GH909,仅仅反应L(+洗)发生并且更多的/Laves最容易溶解的形式。因此,GH909对团结裂开更敏感。预言HAZliquation,裂开的视觉FORTRAN过程被开发,并且NbC的宪政的liquation被模仿。作为在liquation以前的NbC的显示出的、稳固的溶解,减少,和起始的液体与热周期的率拍摄增加。热周期的更高的率支持融化邻近液体电影的矩阵并且由liquid-to-模式推迟液体的团结。因此,更多的剩余液体电影在最容易溶解的点留下,它将支持HAZmicrofissuring。原来的谷物尺寸和山峰温度的增加也支持liquation。最后,这些结论被热韧性测试间接地验证。
简介:LowfieldNMRtechniquewasappliedtoinvestigatethehydrationofcementpasteswithdifferentwatertocementratiosoradditionofsuperplasticizer.Asanondestructivemethod,thistechniquecanbeusedtomonitorthehydrationkineticsprocessbyfollowingthechangesoflongitudinalrelaxationtime(T1)ofwaterconstrainedinthepastes.TheexperimentalresultsindicatethattheT1distributionsofwaterinthefreshpastenormallyexhibitebimodaldistribution,wherethelargepeakiscorrespondingtothefreewaterwhilethesmalloneiscontributedbythewaterstoredintheflocculations.TimedependenceoftheweightedaverageT1hasagoodagreementwiththehydrationprocessandcouldbedividedintofourstages,ie,initialperiod,dormantperiod,acceleratedperiodandsteadyperiod.Thehydrationmechanismofeachstagewasdescribedbasedonthetheoryofcementchemistry.Inaddition,thetotalsignalintensity,whichisproportionaltothecontentofthephysicallyboundwaterinthesamples,decreasesuccessivelyduringthehydrationreflectingtheconsumptionofphysicallyboundwaterbyhydrationreactions.
简介:Dryseparationofironmineralfromlow-gradecoal-serieskaolininHubeiProvinceofChinawasinvestigated.ThestructureandchemicalcompositionofthekaolinoreweredeterminedbyX-raydiffraction(XRD)andX-rayFluorescence(XRF)analyses.Thenarrowparticlesizerangeclassification,drymagneticseparationandcalcinationwerecarriedouttoevaluatetheparticlesizedistribution,andtherelationbetweenthecontentofironandthewhiteness.Experimentalresultsrevealedthatthehighestcontentofiron(3.70%)inkaolinorewasintheparticlesizerangefrom60to74μm,andpyritewasthemainoccurrenceofironinthekaolinore.Drymagneticseparationshowedthattheremovalrateofironinkaolinorecouldbeincreasedobviouslyaftercalcination,andtherateofironremovalwas60%intheparticlesizerangefrom60to74μm.Aspyritecanbetransformedintohematitethroughcalcination,thermodynamicstudiesandXRDanalysisshowedthatthemaximumcontentofhematitewasobtainedat900℃,whichwouldbemorebeneficialtomagneticseparation.