钢材种类和变形的基础知识

BasicKnowledgeofSteelandPlasticMechanics基础钢和塑性变形知识2Contents1.SteelMechanicalpropertiesWorldwidesteelgradesAdvancedhighstrengthsteel(AHSS)2.PlasticmechanicsSheetdeformationmodesForminglimitsYieldcriteria3Introductiontoelasticityandplasticity1.固体材料受外力作用产生变形，从变形开始到破坏一般要经历两个阶段：弹性变形(elasticdeformation)和塑性变形(plasticdeformation)。2.外力卸载后，弹性变形能够完全消失，而塑性变形不能消失。3.弹性变形和塑性变形的机理：材料原子之间的作用力平衡。4.位错(dislocation)理论。5.强化机制(workhardeningmechanism)。Dislocationmovement4UniaxialtensiletestGB/T228金属材料室温拉伸试验方法EN10002-1Metallicmaterials-Tensiletest-Part1:testmethod(inambienttemperature)Typicaltensiletestpiece5Engineeringstress-straincurve6Engineeringstress-straincurve7StrengthandDuctilityStrengthparametersEngineeringstressEngineeringstrainElongationReductionofareaDuctility8Truestress-straincurveTruestressTruestrain9Workinghardening(strainhardening)Strainhardeningexponent(n-value)10Influenceofstrain-hardeningexponentn3n2n111Anisotropy(R-value)Widthstrain:εw=ln(w/w0)Thicknessstrain:εt=ln(t/t0)R=εw/εtPlanaranisotropyratioNormalplasticanisotropyratio12StrainratesensitivityStrainrateStrainratesensitivityexponentStrainratesensitivityhasacrucialinfluenceontheresearchofcrashresistanceandhigh-speedstampingformability.13Worldwidesteelgrades14Worldwidesteelgrades15CommonsteeltypesandevolvingAHSStypesInterstitialfree(IF)steelsMildsteelsBakehardenable(BH)steelsIsotropic(IS)steelsCarbon-manganese(CM)steelsHigh-strengthlow-alloy(HSLA)steelsDualphase(DP)steelsTransformationinducedplasticity(TRIP)steelsComplexphase(CP)steelsMartensitic(Mart)steels16Strengtheningmechanism17HSLAsteel18GradesofHSLAsteelinEU19ApplicationofHSLAsteel20Dualphase(DP)steel21EUsteelgradesComparisonEuropeansteelgrades(Mildsteel,HSLA,Dual-Phase)01002003004005006007008009001000Tensilestrength;Yieldstrength[MPa]Rmmax350400410440450480510530550600620620650700760700900Rmmin.270270270270340370390400430430460480510550600600780Remin.140140140170240280315320355360400420460500550320450Remax.210330280360310360410460500400550DC04DD14DC01DD11H240LAH280LAS315MCH320LAS355MCH360LAH400LAS420MCS460MCS500MCS550MCDP590/DP60DP780/DP80Legend:ColdRolledHotRolledDualPhasecoldrolled(valuesfromARCELOR)Notfornewproducts!:AvailibilitytobeclarifiedFromClausUnruh22DimensionavailabilityAvailabilitycheckmaterialsEuropeversusUS–updateNov2006(onlyacc.myinformation;mustbecheckedandconfirmedbyPurchasingdepartment)Materialavailibilityofstandardmaterialsisgiven.MaterialavailibilityofS460MCisdecreasingeveninEurope.MaterialavailibilityofDualPhaseandotherspecialgradesmustcheckedforeachdimensionsMILDSTEEL01MILDSTEEL04EuropeDC01DC04H280LAH320LAS315MCH360LAS355MCH400LAS420MCS460MCS500MCS550MC0.60.70.81.01.21.51.82.02.53.03.54.04.55.0HSLA460HSLA340HSLA380HSLA300HSLA420HSLA500HSLA550HRCRLegend:AvailableinthemarketAvailableinthemarketAvailablefromindividualsteelproducerAvailablefromindividualsteelproducerAvaibilitynotclearAvaibilitynotclearMILDSTEEL01MILDSTEEL04USASTM1008CSASTM1008DDSSAEJ2340CR300XSAEJ2340HR300XSAEJ2340CR340XSAEJ2340HR340XSAEJ2340CR380XSAEJ2340HR380XSAEJ2340CR420XSAEJ2340HR420XSAEJ2340CR490XSAEJ2340HR490XSAEJ2340CR550XSAEJ2340HR550X0.60.70.81.01.21.51.82.02.53.03.54.04.55.0HSLA380HSLA420HSLA500HSLA550HSLA460HSLA340HSLA300FromClausUnruh23DimensionavailabilityAvailabilitycheckmaterialsEuropeversusChina–updateNov2006(onlyacc.myinformation;mustbecheckedandconfirmedbyPurchasingdepartment)MILDSTEEL01MILDSTEEL04EuropeDC01DC04H280LAH320LAS315MCH360LAS355MCH400LAS420MCS460MCS500MCS550MC0.60.70.81.01.21.51.82.02.53.03.54.04.55.0HSLA460HSLA340HSLA380HSLA300HSLA420HSLA500HSLA550HRCRLegend:AvailableinthemarketAvailableinthemarketAvailablefromindividualsteelproducerAvailablefromindividualsteelproducerAvaibilitynotclearAvaibilitynotclearMILDSTEEL01MILDSTEEL04ChinaDC01DC04H280LAH320LAS315MCH360LAS355MCH400LAS420MCS460MCS500MCS550MC0.60.70.81.01.21.51.82.02.53.03.54.04.55.0HSLA380HSLA420HSLA500HSLA550HSLA460HSLA300HSLA340Materialavailibilityofstandardmaterialsisgiven.MaterialavailibilityofS460MCisdecreasingevenEurope.MaterialavailibilityofDualPhaseandotherspecialgradesmustcheckedforeachdimensionsFromClausUnruh24StandardthicknessChinavs.JapanNotavailableforthematerialswhoseRe=400MPaNotfrequentlyusedinChinaNOTEForthematerialswithnon-standardthickness,Chinesesteelcompaniescanproducethemaccordingtothecustomer’srequirementifthevolumeisnotlessthan20tonsperbatch.Ifthevolumeislessthan20tonsperbatch,thesteelcompanieswillprobablynotproducethem.0,50,60,81,01,21,51,61,82,02,22,53,03,23,54,0Standardthicknessofsteelsheets&stripsforautomobilestructures1,61,82,02,32,52,62,82,93,23,64,04,55,05,66,00,60,70,80,91,01,21,41,61,82,02,3StandardthicknessofhotrolledhighstrengthsteelsheetsforautomobilestructuresStandardthicknessofcoldrolledhighstrengthsteelsheetsforautomobilestructuresChinaJapan25HSLAsteelgradesoverviewOverviewsteelgrades:HSLA(highstrengthlowalloyed)SteelfamilycoldrolledhotrolledLegend:ExistinggradesafterstandardisationUseonlystandardHSLAsteel(worldwideavailable)H240LAandS460MCwascancelledcausedbysourcingproblemswo