《工业分析 Industrial Analysis》课件-项目六：钢铁分析

项目六：钢铁分析任务一：钢铁种类及制样方法钢铁分类及各元素作用课程：工业分析中文Scenario6:SteelanalysisTask1:TypesofsteelandsamplepreparationmethodsClassificationofSteelandtheEffectsofVariousElementsCourse:IndustrialAnalysisEglish一、钢铁种类钢和铁主成分都是铁，区别是根据含碳量的多少生铁：含C>1.7%钢：含C0.05%~1.7%熟铁：含C<0.05低碳钢：0.05~0.25%中碳钢：0.25~0.60%高碳钢：0.60~1.4%中文一、ClassificationofsteelThemaincomponentofbothsteelandironisiron,andthedifferencebetweenthemistheircarboncontentPigiron:containingC>1.7%Steel:containingC0.05%~1.7%Wroughtiron:containingC<0.05low-carbonsteel：0.05~0.25%mediumcarbonsteel：0.25~0.60%high-carbonsteel：0.60~1.4%Eglish1、生铁

铁矿石和焦炭、石灰石按一定比例配合，经过高温煅烧、冶炼，则铁矿石被焦炭还原，生成粗制的铁，称生铁。反应历程较复杂，可用下式代表：中文1、PigironIronoreismixedwithcokeandlimestoneinacertainproportion,andafterhigh-temperaturecalcinationandsmelting,theironoreisreducedbycoketoproducecrudeiron,whichiscalledpigiron.Thereactionprocessiscomplexandcanberepresentedbythefollowingequation:(removeSiO2)

Ironoremainlycontainsothermetallicornon-metallicimpuritiespresentinsilicatestate.Aftersmelting,mostoftheimpuritiesareconvertedintoslag,separatedandremoved,andasmallamountofimpuritiessuchasC,Mn,Si,S,Pareresidualinpigiron.Eglish2、碳素钢如果将生铁与其他辅助材料配合，进一步冶炼，则杂质被进一步氧化除去，同时控制含碳量降至一定限度，硅锰等元素含量很低，硫磷等杂质降至0.05%以下，则成为铁及碳的合金碳素钢。中文2、carbonsteelIfpigironiscombinedwithotherauxiliarymaterialsforfurthersmelting,impuritiesarefurtheroxidizedandremoved.Atthesametime,thecarboncontentiscontrolledtoacertainlimit,andthecontentofelementssuchassiliconandmanganeseisverylow.Impuritiessuchassulfurandphosphorusarereducedtobelow0.05%,makingitanalloycarbonsteelofironandcarbon.IronorelimestonecokeHightemperaturecombustionpigironauxiliarymaterialssmeltcarbonsteelEglish3、特种钢

若适当提高钢中Si或Mn含量，或加入一定量的Ni，Cr，W，Mo，V，Ti等金属，成为特种钢（铁合金或合金钢）。

加Ni、Cr、W、Ti等又分别称为Ni钢、Cr钢、W钢、Ti钢。加Ni增强钢的强度及韧性，多用于承受冲击或强大压力的制件；含Ni36%铸钢受热时几乎不膨胀，可制精密仪器中文3、SpecialSteel

IftheSiorMncontentinthesteelisappropriatelyincreased,oracertainamountofmetalssuchasNi,Cr,W,Mo,V,Tiareadded,thesteelwillbecomespecialsteel(ferroalloyoralloysteel).

SteelcontainingNi,Cr,W,Ti,andotherelementsisalsoknownasNisteel,Crsteel,Wsteel,andTisteel,respectively.

Nienhancesthestrengthandtoughnessofsteel,whichiscommonlyusedinpartsthatneedtowithstandimpactorstrongpressure;Caststeelcontaining36%Nihardlyexpandswhenheated,makingitsuitableforprecisioninstrumentsEglish

加Cr的钢耐热耐腐蚀性较强，多用于制造滚珠轴承或工具；含Cr12.5-18%的铬钢或含铬0.6-1.75%、Ni1.25%的镍铬钢，又称不锈钢，可制高压锅。

加W的钢有极强的耐热性，受热至白热化仍不软化，常制运转的机件或刀具。

高速切削钢：含W15–18%、V1–3%中文

ThesteelwithaddedCrhasstrongheatandcorrosionresistance,andismostlyusedformanufacturingballbearingsortools;ChromiumsteelwithCr12.5-18%ornickelchromiumsteelwithCr0.6-1.75%andNi1.25%,alsoknownasstainlesssteel,canbeusedtomakepressurecookers.

SteelwithaddedWhasextremelystrongheatresistanceanddoesnotsoftenevenwhenheatedtowhiteheat.Itiscommonlyusedforoperatingmachineryorcuttingtools.

Highspeedcuttingsteel:containingW15-18%andV1-3%Eglish二、各元素在钢中的形态和作用

1、碳碳是钢铁的主要成分之一，它直接影响着钢铁的性能。碳是区别铁与钢，决定钢号、品级的主要标志。形态：一般含碳增加，钢铁强度和硬度，但韧性和塑性，正是由于碳的存在，才能用热处理方法来调节和改善其机械性能。中文二、Theformsandfunctionsofvariouselementsinsteel

1、CarbonCarbonisoneofthemaincomponentsofsteel,whichdirectlyaffectsitsperformance.Carbonisthemainsymbolthatdistinguishesironfromsteelanddeterminesthegradeofsteel.Generally,asthecarboncontentincreases,thestrengthandhardnessofsteelwilldecrease,butthetoughnessandplasticitywillincrease.Itispreciselybecauseofthepresenceofcarbonthatheattreatmentmethodscanbeusedtoregulateandimprovethemechanicalpropertiesofsteel.forms：freestatecompoundform：Eglish2、硅形态主要以硅化物：FeSi、MnSi、FeMnSi存在在高硅钢中，一部分以SiC存在，有时也形成固熔体或硅酸盐。作用

增强钢的硬度、弹性及强度，提高抗氧化能力及耐酸性促使C以游离态石墨状态，使钢高于流动性，易于铸造中文2、Siliconform：Mainlyexistingintheformofsilicides:FeSi,MnSi,FeMnSiInhighsiliconsteel,aportionofitexistsasSiCandsometimesformsasolidmeltorsilicate.role：

Enhancethehardness,elasticity,andstrengthofsteel,improveitsoxidationresistanceandacidresistancePromoteCtobeinafreegraphitestate,makingthesteelhigherinfluidityandeasiertocastEglish

形态主要以MnS或FeS状态存在若：

使钢产生“热脆性”——有害成分原因：为什么产生热脆性？

FeS的熔点较低，最后凝固，夹杂于钢铁的晶格之间。当加热压制钢铁时，FeS熔融，钢铁的晶粒失去连接作用而脆裂。3、硫国家标准规定，碳素钢硫含量≤0.05%，优质钢硫含量≤0.02%中文

form：MainlyexistinginMnSorFeSstateSulfurcauses"thermalbrittleness"insteel-harmfulcomponentsReason:Whydoessulfurcausesteeltodevelopthermalbrittleness?ThemeltingpointofFeSisrelativelylow,anditsolidifiesduringsteelmaking,withinclusionsbetweenthelatticeofthesteel.Whenheatingandpressingsteel,FeSmelts,andthegrainsofthesteellosetheirconnectionandbecomebrittle.3、SulfurAccordingtonationalstandards,thesulfurcontentofcarbonsteelis≤0.05%,andthesulfurcontentofhigh-qualitysteelis≤0.02%generateconversely，S+FeEglish形态：以Fe2P或Fe3P状态存在

作用磷化铁硬度较强，以至钢铁难于加工，并使钢铁产生“冷脆性”，也是有害杂质。P↑→流动性↑→易铸造，并可避免在轧钢时轧辊与压件粘合4、磷磷含量≤0.06%中文

form：ExistinginFe2PorFe3Pstate

role：Ironphosphidehasastronghardness,makingitdifficulttoprocesssteelandcausingittodevelopcoldbrittleness.Phosphorusisalsoaharmfulimpurityinsteel.P↑→mobility↑→Easytocastandcanavoidadhesionbetweenrollersandpressedpartsduringsteelrolling4、PhosphorusPhosphoruscontent≤0.06%Eglish形态

主要以MnS状态存在，如S含量较低，过量的锰可能组成MnC、MnSi、FeMnSi等，或以固熔体状态存在。作用

增强钢的硬度，减弱延展性，使钢铁具有良好的弹性和耐磨性。5、锰中文form：

ManganesemainlyexistsintheMnSstateinsteel.IftheScontentislow,excessmanganesemayformMnC,MnSi,FeMnSi,etc.,orexistinasolidmeltstate.role：

Manganesecanenhancethehardnessofsteel,weakenitsductility,andmakesteelhavegoodelasticityandwearresistance.

5、ManganeseEglish

综上所述：

C是确定钢铁型号及用途→主要指标

Si、Mn直接影响钢铁性能(有益的)→控制一定量

S、P有害成分→严格降至一定量因此，对于生铁和碳素钢：C、Si、Mn、S、P等五种元素的含量是冶金或机械工业化验室日常生产控制的重要指标.中文Insummary:Cistodeterminethetypeandpurposeofsteel→mainindicatorsSiandMndirectlyaffecttheperformanceofsteel(beneficial)→controlacertainamountSandPareharmfulcomponents→strictlyreducetoacertainamountTherefore,forpigironandcarbonsteel,thecontentofC,Si,Mn,S,andPisanimportantindicatorfordailyproductioncontrolinmetallurgicalormechanicalindustrylaboratoriesEglish项目六：钢铁分析任务二：钢铁中碳的测定钢铁中碳的测定课程：工业分析中文Scenario6:SteelanalysisTask2:DeterminationofcarboninsteelDeterminationofcarboninsteelCourse:IndustrialAnalysisEglish一、钢铁中碳的测定方法介绍碳的存在形式游离碳：不溶于酸化合碳：能溶于酸而破坏测定各种形态的碳属于相分析；在成分分析中，一般钢样只测定总碳量。生铁试样除测定总碳量外，常分别测定游离碳和化合碳的含量。中文一、IntroductiontothedeterminationmethodofcarboninsteelTheexistenceformofcarbonFreecarbon:insolubleinacidsCompoundcarbon:candissolveinacidandbedestroyedTheoperationofmeasuringvariousformsofcarbonbelongstophaseanalysis;Incompositionanalysis,generallyonlythetotalcarboncontentismeasuredforsteelsamples.Inadditiontomeasuringthetotalcarboncontent,thecontentoffreecarbonandcombinedcarboninpigironsamplesisoftenmeasuredseparately.Eglish总碳量的测定方法有很多，但通常都是将试样置于高温氧气流中燃烧，使之转化为二氧化碳再用适当方法测定，具体又分为以下几种：燃烧-气体容量法燃烧-库仑法燃烧-非水滴定法中文Therearemanymethodsformeasuringtotalcarboncontent,andthemostcommonlyusedmethodisusuallytoburnthesampleinahigh-temperatureoxygenflow,convertitintocarbondioxide,andthenuseappropriatemethodstomeasureit.Specifically,thereareseveraltypes:combustiongascapacitymethodcombustioncoulombmethodcombustionnonaqueoustitrationmethodEglish1、燃烧-气体容量法燃烧-气体容积法是目前国内外广泛采用的标准方法。本法成本低，有较高的准确度，测得结果是总碳量的绝对值。其缺点是要求有较熟练的操作技巧，分析时间较长，对低碳试样测定误差较大。中文1、CombustiongascapacitymethodThecombustiongasvolumemethodiscurrentlywidelyusedasastandardmethodbothdomesticallyandinternationally.Thismethodhaslowcostandhighaccuracy,andthemeasuredresultistheabsolutevalueoftotalcarboncontent.Itsdisadvantageisthatitrequiresproficientoperationalskills,longeranalysistime,andlargermeasurementerrorsforlow-carbonsamples.Measurementprocessstep1●Placethesampleinahigh-temperaturefurnaceandburnitafteroxygenisintroducedStep2ThegeneratedgascontainingCO2iscollectedinameasuringtubetomeasureitsvolume,andthenCO2isabsorbedbyKOHStep3MeasurethechangeingasvolumeinthemeasuringtubebeforeandafterabsorptionStep4CalculatetheresultsbasedonthetemperatureandpressureduringmeasurementEglish2、燃烧-库仑法Ba(ClO4)2+CO2+H2OBaCO3+HClO4中文2、CombustioncoulombmethodBa(ClO4)2+CO2+H2OBaCO3+HClO4Measurementprocessstep1●Placethesampleinahigh-temperaturefurnaceandburnitafteroxygenisintroducedStep2ThegeneratedCO2isabsorbedbyaBa(ClO4)2solution,whichchangesthepHofthesolutionStep3ElectrolysisreturnsthepHofthesolutiontoitsinitialstateStep4CalculatecarboncontentbasedontheamountofelectricityconsumedbyelectrolysisEglish3、燃烧-非水滴定法中文3、CombustionnonaqueoustitrationmethodMeasurementprocessstep1step2step3Placethesampleinahigh-temperaturefurnaceandburnitafteroxygenisintroducedThegeneratedCO2isabsorbedbyanethanolethanolaminesolutionTitrationofabsorptionsolutionwithpotassiumethanolsolutionEglish二、燃烧-气体容量法测定钢铁中碳1、方法原理试样在1200～1300℃的高温O2气流中燃烧，钢铁中的碳被氧化生成CO2:C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2用KOH吸收CO2除硫剂：活性二氧化锰中文二、Determinationofcarboninsteelbycombustiongasvolumetricmethod1、Methodprinciple

ThesampleburnsinanO2airflowathightemperaturesrangingfrom1200to1300℃,andthecarboninthesteelisoxidizedtoproduceCO2:

C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2UsingKOHtoabsorbCO2Desulfurizationagent:activemanganesedioxideEglish图

气体容量法定碳装置1-氧气瓶，2-氧气表，3-缓冲瓶，4、5-洗气瓶，6-干燥塔，7-玻璃磨口塞，8-管式炉，9-燃烧管，10-除硫管，11-容量定碳仪(包括:冷凝管a、量气管b、水准瓶c、吸收瓶d、小旋塞e、三通旋塞f），l2-球形干燥管，13-瓷舟，14-温度自动控制器，15-供氧旋塞2、测定仪器中文GasCapacityCarbonizationDevice1-Oxygencylinder,2-Oxygenmeter,3-Buffercylinder,4,5-Washingcylinder,6-Dryingtower,7-Glassgrindingplug,8-Tubefurnace,9-Combustiontube,10-Sulfurremovaltube,11-Capacitycarbonanalyzer(includingcondensertubea,measuringtubeb,levelbottlec,absorptionbottled,smallcocke,three-waycockf),12-Sphericaldryingtube,13-Porcelainboat,14-Temperatureautomaticcontroller,15-Oxygensupplycock2、measuringinstrumentEglish3、测定试剂氢氧化钾吸收剂溶液（400g/L）；除硫剂活性二氧化锰（粒状）或钒酸银；酸性氯化钠溶液（250g/L）；助熔剂：锡粒（或锡片）、铜、氧化铜、纯铁粉；高锰酸钾溶液（40g/L）；甲基橙指示剂（2g/L）。中文3、TestingreagentsPotassiumhydroxideabsorbentsolution(400g/L);Sulfurremovalagent:activemanganesedioxide(granular)orsilvervanadate;Acidicsodiumchloridesolution(250g/L);Fluxes:tinparticles(ortinsheets),copper,copperoxide,pureironpowder;Potassiumpermanganatesolution(40g/L);Methylorangeindicator(2g/L).Eglish4、测定步骤将炉温升至1200～1350℃，检查管路及活塞是否漏气，装置是否正常，燃烧标准样品，检查仪器及操作。称取适量试样置于瓷舟中，将适量助熔剂覆盖于试样上面，打开玻璃磨口塞，将瓷舟放入瓷管内，用长钩推至高温处，立即塞紧磨口塞。预热lmin，按照定碳仪操作规程操作，测定其读数(体积或含量)。打开磨口塞，用长钩将瓷舟拉出，即可进行下一试样分析。中文4、Measurementsteps

Raisethefurnacetemperatureto1200-1350℃,checkforleaksinthepipelinesandpistons,ensurethedeviceisfunctioningproperly,burnstandardsamples,andinspectinstrumentsandoperations.

Weighanappropriateamountofsampleandplaceitinaporcelainboat.Coverthesamplewithanappropriateamountofflux,opentheglassgrindingplug,placetheporcelainboatintotheporcelaintube,usealonghooktopushittoahightemperature,andimmediatelytightenthegrindingplug.Preheatforlmin,followtheoperatingproceduresofthecarbonanalyzer,andmeasureitsreading(volumeorcontent).Openthegrindingplugandpullouttheporcelainboatwithalonghooktoproceedwiththenextsampleanalysis.Eglish5、结果计算当固定称样量如0.2500g、0.5000g或1.000g时的含碳量，其结果可按下式计算：

f—温度、压力补正系数中文5、resultcalculation

Whenthefixedsamplesizeis0.2500g,0.5000g,or1.000g,thecarboncontentresultcanbecalculatedusingthefollowingformula:

f—TemperatureandpressurecorrectioncoefficientsEglish项目六：钢铁分析任务二：钢铁中碳的测定燃烧-气体容量法测定钢铁中碳课程：工业分析中文Scenario6:SteelanalysisTask2:DeterminationofcarboninsteelDeterminationofcarboninsteelbycombustiongasvolumetricmethodCourse:IndustrialAnalysisEglish1、方法原理试样在1200～1300℃的高温O2气流中燃烧，钢铁中的碳被氧化生成CO2:C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2中文1、Methodprinciple

ThesampleburnsinanO2airflowathightemperaturesrangingfrom1200to1300℃,andthecarboninthesteelisoxidizedtoproduceCO2:C+O2=CO24Fe3C+13O2=4CO2+6Fe2O3

Mn3C+3O2=CO2+Mn3O3FeS+5O2=Fe3O4+3SO23MnS+5O2=Mn3O4+3SO2Eglish生成的CO2与过剩的O2经导管引入量气管，测定容积，然后通过装有KOH溶液的吸收器，吸收其中的CO2CO2十2KOH=K2CO3十H2O剩余的O2再返回量气管中，根据吸收前后容积之差，得到CO2的容积，据此计算出试样中碳的质量分数。中文

First,introducethegeneratedmixtureofCO2andexcessO2intothevolumetrictube,measurethevolumeofthemixture,andthenintroducethemixtureintoanabsorbercontainingKOHsolutiontoabsorbtheCO2inside:

CO2+2KOH=K2CO3+H2O

TheremainingO2isreturnedtothemeasuringtube,andbasedonthedifferenceinvolumebeforeandafterabsorption,thevolumeofCO2isobtained.Basedonthis,themassfractionofcarboninthesampleiscalculated.Eglish图

气体容量法定碳装置1-氧气瓶，2-氧气表，3-缓冲瓶，4、5-洗气瓶，6-干燥塔，7-玻璃磨口塞，8-管式炉，9-燃烧管，10-除硫管，11-容量定碳仪(包括:冷凝管a、量气管b、水准瓶c、吸收瓶d、小旋塞e、三通旋塞f），l2-球形干燥管，13-瓷舟，14-温度自动控制器，15-供氧旋塞2、测定仪器中文2、measuringinstrumentGasCapacityCarbonizationDevice1-Oxygencylinder,2-Oxygenmeter,3-Buffercylinder,4,5-Washingcylinder,6-Dryingtower,7-Glassgrindingplug,8-Tubefurnace,9-Combustiontube,10-Sulfurremovaltube,11-Capacitycarbonanalyzer(includingcondensertubea,measuringtubeb,levelbottlec,absorptionbottled,smallcocke,three-waycockf),12-Sphericaldryingtube,13-Porcelainboat,14-Temperatureautomaticcontroller,15-OxygensupplycockEglish3、测定试剂氢氧化钾吸收剂溶液（400g/L）；除硫剂活性二氧化锰（粒状）或钒酸银；酸性氯化钠溶液（250g/L）；助熔剂：锡粒（或锡片）、铜、氧化铜、纯铁粉；高锰酸钾溶液（40g/L）；甲基橙指示剂（2g/L）。中文3、TestingreagentsPotassiumhydroxideabsorbentsolution(400g/L);Sulfurremovalagent:activemanganesedioxide(granular)orsilvervanadate;Acidicsodiumchloridesolution(250g/L);Fluxes:tinparticles(ortinsheets),copper,copperoxide,pureironpowder;Potassiumpermanganatesolution(40g/L);Methylorangeindicator(2g/L).Eglish4、测定步骤将炉温升至1200～1350℃，检查管路及活塞是否漏气，装置是否正常，燃烧标准样品，检查仪器及操作。称取适量试样置于瓷舟中，将适量助熔剂覆盖于试样上面，打开玻璃磨口塞，将瓷舟放入瓷管内，用长钩推至高温处，立即塞紧磨口塞。预热lmin，按照定碳仪操作规程操作，测定其读数(体积或含量)。打开磨口塞，用长钩将瓷舟拉出，即可进行下一试样分析。中文4、Measurementsteps

Raisethefurnacetemperatureto1200-1350℃,checkforleaksinthepipelinesandpistons,ensurethedeviceisfunctioningproperly,burnstandardsamples,andinspectinstrumentsandoperations.

Weighanappropriateamountofsampleandplaceitinaporcelainboat.Coverthesamplewithanappropriateamountofflux,opentheglassgrindingplug,placetheporcelainboatintotheporcelaintube,usealonghooktopushittoahightemperature,andimmediatelytightenthegrindingplug.Preheatforlmin,followtheoperatingproceduresofthecarbonanalyzer,andmeasureitsreading(volumeorcontent).Openthegrindingplugandpullouttheporcelainboatwithalonghooktoproceedwiththenextsampleanalysis.Eglish5、测定注意事项助熔剂中含碳量一般不超过0.005%样品的放置要均匀地铺在燃烧舟中定碳仪应装置在室温较正常的地方(距离高温炉约300～500mm)更换水准瓶所盛溶液、玻璃棉、除硫剂、氢氧化钾溶液后，均应作几次高碳试样，使二氧化碳饱和后，才可进行试样测定。中文5、MeasurementprecautionsThecarboncontentinthefluxgenerallydoesnotexceed0.005%ThesampleshouldbeplacedevenlyinthecombustionboatThecarbonanalyzershouldbeinstalledinaplacewithrelativelynormalroomtemperature(about300-500mmawayfromthehigh-temperaturefurnace)Afterreplacingthesolution

inthelevelingbottle,glasswool,sulfurremovalagent,andpotassiumhydroxidesolution,severalhighcarbonsamplecombustionshouldbecarriedouttosaturatecarbondioxideinthesesubstancesbeforesampledeterminationcanbecarriedout.Eglish对测定含硫量较高的试样(大于0.2%)，应增加除硫剂量或增加一个除硫管。吸收器、水准瓶内溶液以及混合气体三者的温度应基本相同，否则将产生正负空白值。如分析完高碳试样后，应空烧一次，才可以接着做低碳试样分析。当洗气瓶中硫酸体积显著增加及二氧化锰变白时，说明已失效，应及时更换。观察试样是否完全燃烧，如燃烧不完全，需重新分析。中文Forsampleswithhighsulfurcontent(greaterthan0.2%),thesulfurremovaldoseshouldbeincreasedorasulfurremovaltubeshouldbeadded.Thetemperatureoftheabsorber,thesolutioninthelevelbottle,andthemixedgasshouldbebasicallythesame,otherwisepositiveandnegativeblankvalueswillbegenerated.Afteranalyzingthehighcarbonsample,itshouldbeburnedoncebeforeproceedingwiththeanalysisofthelowcarbonsample.Whenthevolumeofsulfuricacidinthegascylindersignificantlyincreasesandmanganesedioxideturnswhite,itindicatesthatithasfailedandshouldbereplacedinatimelymanner.Observewhetherthesampleiscompletelyburned.Ifthecombustionisincomplete,reanalysisisrequired.Eglish炉子升温应开始慢，逐步加速，以延长硅碳棒寿命。分析前，应先检查仪器各部分是否漏气。工作开始前及工作中，均应燃烧标准样品，判定工作过程中仪器的准确性。吸收前后观察刻度的时间应一致。吸收后观察刻度时，量气管及水准瓶内液面与视线应处在同一水平线上。吸收器中氢氧化钾溶液使用久后也应进行更换，一般在分析2000次后更换，否则吸收效率降低，使测定结果偏低。测定中应记录温度与大气压力，以确定补正系数f。如附录八所示。中文Theheatingofthefurnaceshouldstartslowlyandthengraduallyacceleratetoextendthelifespanofthesiliconcarbiderod.Beforeanalysis,eachpartoftheinstrumentshouldbecheckedforairleakage.Beforeandduringwork,standardsamplesshouldbeburnedtodeterminetheaccuracyoftheinstrumentsusedduringtheworkprocess.Whenobservingthescaleafterabsorption,theliquidlevelinthemeasuringtubeandlevelbottleshouldbeonthesamehorizontalline.Thepotassiumhydroxidesolutionintheabsorberisusuallyreplacedafter2000analyses,otherwisetheabsorptionefficiencywilldecrease,resultinginlowermeasurementresults.Duringthemeasurement,temperatureandatmosphericpressureshouldberecordedtodeterminethecorrectioncoefficientf.ThecorrectioncoefficientsareshowninAppendix8.Eglish6、结果计算当固定称样量如0.2500g、0.5000g或1.000g时的含碳量，其结果可按下式计算：

f—温度、压力补正系数中文6、resultcalculation

Whenthefixedsamplesizeis0.2500

g,0.5000

g,or1.000

g,thecarboncontentcanbecalculatedusingthefollowingformula:：

f—TemperatureandpressurecorrectioncoefficientsEglish项目六：钢铁分析任务三：钢铁中硫的测定燃烧-碘量法测定钢铁中硫课程：工业分析中文Scenario6:SteelanalysisTask3:DeterminationofsulfurinsteelDeterminationofsulfurinsteelbycombustioniodimetryCourse:IndustrialAnalysisEglish一、燃烧-碘量法测定钢铁中硫将钢铁试样于1250～1350℃的高温下通氧燃烧，使硫全部转化为二氧化硫，将生成的二氧化硫用淀粉溶液吸收，用碘酸钾标准溶液滴定至浅蓝色为终点:

燃烧：4FeS+O2=2Fe2O3+4SO23MnS+5O2=Mn3O4+3SO2

吸收：SO2+H2O=H2SO3

滴定：KIO3+5KI+6HCl=3I2+6KCl+3H2OH2SO3+I2+H2O=H2SO4+2HI中文一、DeterminationofsulfurinsteelbycombustioniodimetryThesteelsampleisignitedwithoxygenatahightemperatureof1250-1350℃,andallsulfurinthesteelisconvertedintosulfurdioxide.Thegeneratedsulfurdioxideisabsorbedwithstarchsolutionandtitratedwithpotassiumiodatestandardsolutionuntiltheendpointislightblue：

combustion：4FeS+O2=2Fe2O3+4SO23MnS+5O2=Mn3O4+3SO2

absorption：SO2+H2O=H2SO3titration：KIO3+5KI+6HCl=3I2+6KCl+3H2OH2SO3+I2+H2O=H2SO4+2HIEglish1、主要试剂碘酸钾标准滴定溶液：[c(1/6KI03)=0.01000mol/L、0.001000mol/L、0.0002500mol/L]淀粉吸收液(10g/L)助熔剂：二氧化锡和还原铁粉以3+4比例混匀中文1、MainreagentsPotassiumiodatestandardtitrationsolution：[c(1/6KI03)=0.01000mol/L、0.001000mol/L、0.0002500mol/L]Starchabsorptionsolution(10g/L)

Flux:Mixtindioxideandreducedironpowderina3+4ratioEglish2、主要仪器定硫仪的滴定部分装置1-球形管，2-吸收杯，3-滴定管中文2、MaininstrumentsDevicediagramofthetitrationsectionofthesulfuranalyzer1-Sphericaltube,2-Absorptioncup,3-BuretteEglish3、测定步骤将炉温升至1200～1350

C，检查装置是否正常，于定硫吸收杯中加入淀粉吸收液（硫小于0.01%用低硫吸收杯，加20mL吸收液；硫大于0.01%用高硫吸收杯，加60mL吸收液），以600～1500mL/min的流速通氧，用碘酸钾标准滴定溶液滴定至浅蓝色不褪，作为终点色泽，关闭氧气。中文3、Measurementsteps

Raisethefurnacetemperatureto1200-1350°C,checkifthedeviceisfunctioningproperly,addstarchabsorptionsolution(forsulfurlessthan0.01%,usealowsulfurabsorptioncup,add20mLofabsorptionsolution;forsulfurgreaterthan0.01%,useahighsulfurabsorptioncup,add60mLofabsorptionsolution)toafixedsulfurabsorptioncup,passoxygenataflowrateof600-1500mL/min,titratewithpotassiumiodatestandardtitrationsolutionuntillightbluedoesnotfadeastheendpointcolor,andturnoffoxygen.Eglish称取适量试样，置于瓷舟中，加入适量助熔剂，将瓷舟推至高温处，预热0.5～1.5min，通氧，控制氧速为1500～2000mL/min，燃烧后的混合气体导入吸收杯中，使淀粉吸收液蓝色开始消褪，立即用碘酸钾标准溶液滴定并使液面保持蓝色，当吸收液褪色缓慢时，滴定速度也相应减馒，直至吸收液的色泽与原来的终点色泽相同，间歇通气后，色泽不变即为终点。中文

Weighanappropriateamountofsample,placeitinaporcelainboat,addanappropriateamountofflux,pushtheporcelainboattoahightemperature,preheatfor0.5-1.5minutes,introduceoxygen,controltheoxygenrateto1500-2000mL/min,andintroducethemixedgasaftercombustionintotheabsorptioncup,sothatthebluecolorofthestarchabsorptionliquidbeginstofade.Immediatelytitratewithpotassiumiodatestandardsolutionandkeeptheliquidsurfaceblue.Whentheabsorptionliquidfadesslowly,thetitrationspeedalsodecreasesaccordingly,Untilthecoloroftheabsorptionsolutionisthesameastheoriginalendpointcolor,andafterintermittentventilation,thecolorremainsunchanged,whichistheendpoint.

Eglish4、结果计算T—碘酸钾标准溶液对硫的滴定度，g/mL；V—滴定试样所消耗碘酸钾标准溶液的体积，mL；V0—滴定空白时所消耗碘酸钾标准溶液的平均体积，mL；m—试料的质量，g。中文4、resultcalculationT—Titrationofpotassiumiodatestandardsolutionforsulfur，g/mL；V—Thevolumeofpotassiumiodatestandardsolutionconsumedintitratingthesample，mL；V0—Theaveragevolumeofpotassiumiodatestandardsolutionconsumedduringtitrationofblank，mL；m—Qualityoftestmaterials，g。Eglish项目六：钢铁分析任务三：钢铁中硫的测定钢铁中硫的测定方法介绍课程：工业分析中文Scenario6:SteelanalysisTask3:DeterminationofsulfurinsteelIntroductiontothedeterminationmethodofsulfurinsteelCourse:IndustrialAnalysisEglish一、钢铁中硫的危害硫是钢铁中有害元素，使钢铁产生热脆性钢铁中硫燃烧生成SO2或SO3，会污染环境，腐蚀设备钢铁中硫在高温下遇到氢会化合生成H2S，该气体是剧毒气体，对人体有害中文

一、ThehazardsofsulfurinsteelSulfurisaharmfulelementinsteel,causingittodevelopthermalbrittlenessThecombustionofsulfurinsteelgeneratesSO2orSO3,whichcanpollutetheenvironmentandcorrodeequipmentSulfurinsteelwillreactwithhydrogenathightemperaturestoformH2S,ahighlytoxicgasthatisharmfultohumanhealthEglish二、测定方法重量法燃烧法燃烧-滴定法燃烧-分光光度法燃烧-电导法燃烧-红外光谱法中文二、MeasurementmethodgravimetricmethodCombustionCombustiontitrationmethodCombustionspectrophotometryCombustionconductivitymethodCombustioninfraredspectroscopyEglish1、重量法因硫酸钡沉淀溶解而产生负偏差测定过程第一步第二步第三步样品用酸分解成硫酸盐试样溶液加入氯化钡使生成硫酸钡沉淀过滤沉淀，洗涤灼烧，称重计算中文1、gravimetricmethodNegativedeviationcausedbydissolutionofbariumsulfateprecipitationstep1step2step3

ThesampleisdecomposedintosulfatesusingacidAddingBaCl2tothesamplesolutiontogenerateBaSO4

precipitateFiltersediment,washandburn,weighandcalculateMeasurementprocessEglish2、燃烧法测定依据是让钢铁燃烧，其中硫转化为SO2而测定，方法缺点是硫的回收率低于90%，有时甚至更低，为提高测定准确性，常需注意以下几点：燃烧温度要高：1450~1510℃燃烧时间足够注意减少SO2的吸附选用优良的助熔剂防止SO2的接触转化中文2、CombustionmethodThedeterminationisbasedonthecombustionofsteel,inwhichsulfurisconvertedintoSO2.Thedisadvantageofthismethodisthattherecoveryrateofsulfurislessthan90%,sometimesevenlower.Toimprovetheaccuracyofthedetermination,thefollowingpointsshouldbenoted:Thecombustiontemperatureshouldbehigh:1450-1510℃SufficientcombustiontimePayattentiontoreducingtheadsorptionofSO2SelectexcellentfluxesPreventthecontactconversionofSO2Eglish（1）燃烧-滴定法碘量法：SO2经水吸收成为亚硫酸，用碘滴定酸碱法：SO2经过氧化氢水溶液吸收转化为硫酸，用碱滴定硼酸钠法：用0.2%硫酸钾和4%过氧化氢水溶液吸收SO2，用硼酸钠滴定生成的硫酸中文（1）CombustiontitrationmethodIodometricmethod:SO2isabsorbedbywatertoformsulfite,whichistitratedwithiodineAcid-basetitrationmethod:SO2isabsorbedandconvertedintosulfuricacidbyhydrogenoxideaqueoussolution,andthentitratedwithalkaliSodiumboratemethod:AbsorbSO2with0.2%potassiumsulfateand4%hydrogenperoxideaqueoussolution,anddetermineth