简介:Thestudyintroducesthechemicalcomposition,mechanicalproperties,physicalpropertiesandproductionprocessesoftheFe-23Mn-2Al-Vausteniticsteel.Investigationsweremadeintotheformationofcracksinthehot-rolledFe-23Mn-2Al-Vsteelplates,withopticalmicroscopy(OM),scanningelectronmicroscopy(SEM)andenergydispersivespectrum(EDS).Theresultshaveshownthatintergranularoxidationinthereheatingfurnaceisthemaincauseofthecracksonthesurfaceofthehot-rolledsteelplates.Thesurfacecrackingcanbelargelyavoidedbycontrollingtheremainingoxygencontentinthereheatingfurnaceandimprovingcontinuouscasting(CC)processestoincreasethethicknessoffineequiaxedgrainlayerofthesteelslabs.
简介:Hydrogen,asatemporaryelementintitaniumalloys,isverygoodincontrollingmicrostructure.ThemicrostructureandphasetransformationofTi6A14ValloyareaffectedbytheamountofTiH,addedintothemeltofTi6A14Valloyduringtheinductionskullmelting(ISM)process.Thisprocess,calledmelthydrogenation,wasstudiedinthispaperthroughtheuseofopticalmicroscopy,scanningelectronmicroscopy(SEM)andtransmissionelectronmicroscopy(TEM).Theresultsareasfollows:aftermelthydrogenation,boththesolidificationmacrostructureandmicrostructureofTi6A14Valloyarerefined;theαphaseprecipitatesinalamellarformwiththeresidualβphasefromthegrainboundaries;δ-hydridesprecipitateduringthesolidificationprocessasaresultoftheexistenceofhydrogen.TheSphasewithanF.C.C.structurecanbeobservedbyTEMintheαphaselaminaeofspecimenswith1.25%TiH2.Inaddition,thedependenceofthemicrohardnessofspecimensontheweightpercentageofTiH,addedtothemeltduringtheISMprocesswasalsostudied.
简介:为提高涟钢薄板产品质量,2007年,公司决定对烧结原料进行分开配矿,杂质含量低,烧结性能好的原料进280m2烧结机,所有利废物全部进130m2烧结机和180m2烧结机(以下简称130+180m2),导致利废物由8%提高到18%;同时为了提高烧结矿品位,精粉比例从35%提高到45%。在此情况下,130+180m2烧结机烧结料透气性变差,利用系数下降,能耗升高,保矿压力增大。生产实践证明,提高烧结混合料温度,可以显著减少过湿层的发生,改善料层的透气性能,为实行厚料层烧结提供了有力保障,有效的降低了烧结固体燃料的消耗,提高了烧结生产率。涟钢130+180m2烧结机原在混合料仓安装了蒸汽预热,但预热效果达不到最佳状态。因此,为进一步运用余热回收蒸汽来预热混合料新技术,根据本车间现有的工艺状况,分别在130+180m2分料仓安装蒸汽喷头,通过对分料仓的改造,合理利用余热蒸汽,有效的提高了混合料的温度,取得了良好的经济效益。