简介:Lightweightdesignisoneofthedevelopmenttrendsoftheautomobileindustry.AneffectivewaytoachievelightweightautobodiesistouseAHSS(advancedhighstrengthsteel)forthesafetycomponentsofautomobiles.ThisstudyhastakendoorsillreinforcementsmadeofmartensiteAHSSastheobject,andperformedresearchontheAHSSrollformingtechnologiesandprototypedevelopmentoftypicalasymmetricopencomponents.Bymeansoffiniteelementanalysis(FEA)andsimulation,studieshavebeencarriedoutonthespringbackandedgewavedefectsduringAHSSrollforming,andanoptimizedprocessdesignhasbeenachieved.Thegenerationmechanismsofverticalbows,horizontalcambers,twists,pre-punchedholedistortionandcutendflarehavebeenanalyzed,andsolutionstothesedefectshavebeengiven.Inaddition,tesingoftherollformingprocessforAHSShasbeenconductedandtypicalsampleswithrequireddimensionalaccuracyhavebeenmanufactured.Thisstudyhasprovidedtechnicalsupportforthelarge-scaleapplicationofAHSS.
简介:Toaddressthephenomenonofsparkingduringtheedgeinductionheatingprocessinhotstripmills,thispaperusesnumericalsimulationtosystematicallyinvestigatethekeyfactorsinfluencingsparkingandtheireffects.Thedistributionofinducedcurrentdensityinthesteelplateaboverollerconveyortableduringtheheatingprocessiscalculatedandcomparedunderdifferentconditions,includingtherelativepositionsofthesteelplateandinductioncoil,thewidthofthesteelplate,andchangesinload.Theresultsshowthatwhenanarrowsteelplateisheatedorthesteelplateshiftstothesideoftheinductioncoil,sparkingbetweenthesteelplateandrollerconveyorismorelikelytooccur.
简介:Thisarticleistrytoexplainoranalyzethekeytechnologiesofcontrollingthesurfacequalityoflowcarbonsteelascaststripthroughinvestigationofinterfaceheattransferbetweensolidifiedshellandliquidsteel.Theoneofthekeytechnologiesofcontrollingsurfacequalityoflowcarbonsteelascaststripisthroughthecastingrollsurfacetextureinordertoachievethehomogeneoussolidificationonthecastingroll.Anotheristhroughformingathinfilmonthecastingrollsurfaceinordertoachieveabalancebetweenrapidsolidificationandhomogeneoussolidification.Thisfilmformedbetweenthetwinrollandthemoltensteelcanbecontrolledbyadjustingthechemicalcompositionandinclusioninliquidsteelthroughcontrollingtheamountofall[O]andfree[O].
简介:Chinaisanimportantcountryinironandsteelindustry.Powerelectronicsconvertersarewidelyused.Forthecoldrollingmillsofhighspeed,AC-DC-ACconvertersshouldbeused.Inthepaper,thedesignandthecontrolsystemofthelargepowerthree-levelAC-DC-ACconverterwithIGCTsisinvestigated,andaback-to-backlargepowerthree-levelAC-DC-ACconverterwithIGCTshasbeengot.Withaseriesexperiments,theperformanceoftheconverterisexamined.Theexperimentresultindicatestheconverterreachesthedesignrequirementanditshowsexcellentperformance.Theconvertersystemhasbeenputintousesafely.ItisestimatedthattheAC-DC-ACconvertersystemwillbeusedinthedrivesystemsforrollingmillsinthenearfuture.
简介:采用Gleeble-1500热模拟机高温压缩试验,研究5A01铝合金在应变速率为0.01~1s^-1、变形温度为350~450℃条件下的流变行为,并利用光学显微镜分析合金在不同压缩条件下的组织形貌特征。结果表明:应变速率和变形温度的变化强烈影响合金流变应力的大小,流变应力随变形温度升高而降低,随应变速率提高而增大。采用双曲正弦形式ARRHENIUS的关系来描述5A01铝合金高温压缩变形时的流变应力行为,获得的材料常数A、a、11和Q分别为0.06831s^-1、0.0094MPa、2.7089和161.14kJ/mol;在应变速率为0.01s^-1叫及变形温度低于400℃条件下变形时,5A01铝合金组织为纤维组织,而当变形温度升高到450℃时,再结晶程度很高,出现大量等轴晶。