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1、ProductsofLORDAudiTT(¥400,000-700,000)AudiR8(¥2320,000-2780,000)BuickLucerne(¥300,000-500,000)Ferrari599GTB(¥5000,000)HoldenHSVCommodore(¥1200,000-2000,000)地势MRF-122EGMagneto-RheologicalFluid•FastResponseTime–respondsinstantlyandreversiblytochangesinamagneticfield.•Dyn
2、amicYieldStrength–provideshighyieldstrengthinthepresenceofamagneticfieldandverylowyieldstrengthintheabsenceofamagneticfield;allowsforawiderangeofcontrollability.•TemperatureResistant–performsconsistentlythroughoutabroadtemperaturerange,meetingtherequirementsofdemandin
3、gapplicationssuchasautomotiveshockabsorbers.•HardSettlingResistant–provideshighresistancetohardsettling;easilyredispersed(重分散).•Non-Abrasive(零磨损)–formulatedtonotabrade(损伤)thedevicesinwhichtheMRfluidisused.FeaturesandBenefitsWhataremagnetorheologicalfluids?Magnetorhe
4、ologicalfluidsbelongtothegroupofsocalledcontrollablefluids.Thismeansthattheyexhibitasignificantchangeintheirrheologicalbehaviourwhenanexternalmagneticfield(外部磁场)isappliedtothem.Theyareindeedcomposedofmicron-sizedmagneticparticles(微米级磁粒),locatedinsidealiquidcarrier,thatf
5、ormchain-likestructureswhentheexternalmagneticfieldisapplied,resultinginanincreaseoftheapparentviscosity(粘性)ofthefluid(Fig.1and2).Fig.1:Chain-likestructuresformationintheMRfluidunderanexternallyappliedmagneticfield(fromLORDcorporation)Fig.2:ChainsformationinadropofMRfl
6、uid(fromISCFraunhofer)TherheologicalbehaviourofMRfluidsisoftenrepresentedasaBinghamplasticmodelwithavariableyieldstrengthdependingontheappliedmagneticfieldH(Fig.3aand3b).Theflowisgovernedbytheequation:whereistheshearstress,istheshearstrainandistheviscosityofthefluid.The
7、operatingrangeistheshadedareainFig.3c.Belowtheyieldstress(atstrainsoftheorderof10-3),theMRfluidbehavesviscoelastically:WhereGisthecomplexmaterialmodulus.ThismodelisalsoagoodapproximationforMRdevices.However,theactualbehaviourismorecomplicatedandincludesstiction(静摩擦)andh
8、ysteresis(磁滞现象)suchsuchasshowninFig.3.dFig.3:(a)and(b)Binghamplasticmodel,(c)Operatingrange,(d)Hystereticbehav