鎂合金應(yīng)變率和拉壓非對(duì)稱力學(xué)行為表征及薄壁管吸能特性研究

鎂合金應(yīng)變率和拉壓非對(duì)稱力學(xué)行為表征及薄壁管吸能特性研究摘要：

在逐步提高汽車安全性的背景下，鎂合金作為一種輕質(zhì)高強(qiáng)材料，受到了越來越多的關(guān)注。本文解析了鎂合金應(yīng)變率和拉壓非對(duì)稱力學(xué)行為的表征方法，并研究了其薄壁管吸能特性。通過拉伸試驗(yàn)和壓縮試驗(yàn)得到了常規(guī)應(yīng)變速率下的力學(xué)性能和應(yīng)變率效應(yīng)，同時(shí)探究了鎂合金在不同應(yīng)變率下的應(yīng)變硬化和材料變形行為。論文還研究了不同幾何參數(shù)下的薄壁管吸能性能，建立了鎂合金薄壁管吸能性能的模型，探究了幾何參數(shù)對(duì)吸能性能的影響。

關(guān)鍵詞：鎂合金；應(yīng)變率；拉壓非對(duì)稱力學(xué)行為；薄壁管；吸能性能

Abstract:

Withthegradualimprovementofautomobilesafety,magnesiumalloyshavebecomeahottopicasalightweightandhigh-strengthmaterial.Thispaperanalyzesthecharacterizationmethodsofstrainrateandtension-compressionasymmetricalmechanicalbehaviorofmagnesiumalloys,andstudiestheirenergyabsorptioncharacteristicsofthin-walledtubes.Byconductingtensileandcompressivetests,themechanicalpropertiesandstrainrateeffectsofmagnesiumalloysunderconventionalstrainratesareobtained.Atthesametime,thestrainhardeningandmaterialdeformationbehaviorofmagnesiumalloysunderdifferentstrainratesareexplored.Thepaperalsostudiestheenergyabsorptionperformanceofthin-walledtubeswithdifferentgeometricparameters,establishesamodelfortheenergyabsorptionperformanceofmagnesiumalloythin-walledtubes,andexplorestheinfluenceofgeometricparametersonenergyabsorptionperformance.

Keywords:magnesiumalloy;strainrate;tension-compressionasymmetricalmechanicalbehavior;thin-walledtube;energyabsorptionperformancMagnesiumalloyshavebeenwidelyusedinvariousindustriesduetotheirexcellentmechanicalproperties,lowdensity,andgoodcorrosionresistance.However,theirmechanicalbehaviorunderdifferentstrainratesisstillnotfullyunderstood.Inthisstudy,thestrainratedependenceofthetensileandcompressivepropertiesofmagnesiumalloyswasinvestigated.Theresultsshowedthatthemechanicalpropertiesofmagnesiumalloysexhibitasignificantstrainratesensitivity,andtheirtension-compressionasymmetricalbehaviorbecomesmorepronouncedathigherstrainrates.

Thin-walledtubesmadeofmagnesiumalloyshavebeenusedasenergyabsorptionelementsinmanyapplicationsduetotheirexcellentenergyabsorptionperformance.However,theinfluenceofthegeometricparametersofthin-walledtubesontheirenergyabsorptionperformancehasnotbeenfullystudied.Inthisstudy,theenergyabsorptionperformanceofthin-walledtubeswithdifferentgeometricparameterswasevaluatedexperimentally,andamodelwasestablishedtodescribetheenergyabsorptionperformanceofmagnesiumalloythin-walledtubes.

Theresultsshowedthattheenergyabsorptionperformanceofmagnesiumalloythin-walledtubesisstronglyinfluencedbythegeometricparameters,suchasthetubediameter,wallthickness,andlength.Themodeldevelopedinthisstudycanbeusedtopredicttheenergyabsorptionperformanceofmagnesiumalloythin-walledtubeswithdifferentgeometricparameters.

Inconclusion,thisstudyprovidesacomprehensiveunderstandingofthemechanicalbehaviorofmagnesiumalloysunderdifferentstrainratesandtheenergyabsorptionperformanceofmagnesiumalloythin-walledtubeswithdifferentgeometricparameters.ThefindingsofthisstudyhaveimportantpracticalimplicationsforthedesignanddevelopmentofenergyabsorptionelementsmadeofmagnesiumalloysFurthermore,thepresentstudyidentifiespotentialareasforfutureresearch.Onesuchareaistheinvestigationoftheeffectofsurfacetreatmentsontheenergyabsorptionperformanceofmagnesiumalloythin-walledtubes.Itisknownthatsurfacetreatments,suchasanodizing,canimprovethecorrosionresistanceofmagnesiumalloys.Itremainstobestudiedwhethersuchtreatmentscanalsoimprovetheenergyabsorptioncapabilitiesofthealloy.Additionally,theeffectoftemperatureonthemechanicalbehaviorandenergyabsorptionperformanceofmagnesiumalloysneedstobestudied.Giventhatmagnesiumalloysarehighlysensitivetotemperature,itiscriticaltounderstandtheeffectoftemperatureontheenergyabsorptionbehaviorofmagnesiumalloythin-walledtubes.

Inconclusion,thepresentstudyshedslightonthemechanicalbehaviorandenergyabsorptionperformanceofmagnesiumalloythin-walledtubeswithdifferentgeometricparameters.Thefindingsofthisstudycanbeofsignificantvaluetoresearchersandengineersworkingonthedesignofenergyabsorptionelementsmadeofmagnesiumalloys.ThestudyalsoidentifiespotentialareasforfutureresearchthatcanfurtherenhancetheunderstandingofthecharacteristicsofthematerialanditsapplicationinenergyabsorptionelementsPossiblecontinuation:

Onepotentialareaforfutureresearchistoinvestigatetheeffectofdifferentprocessingmethodsonthemechanicalpropertiesandenergyabsorptionperformanceofmagnesiumalloythin-walledtubes.Thecurrentstudyusedextrudedtubes,butothermethodssuchasrolling,forging,orhot-stampingmayproducedifferentmicrostructuresandtexturesthatcouldaffectthedeformationbehaviorandfracturemodes.Somestudieshaveshownthatsevereplasticdeformationtechniquessuchasequal-channelangularpressingorhigh-pressuretorsioncanrefinethegrainsizeandincreasethestrengthofmagnesiumalloys,buttheireffectonenergyabsorptionhasnotbeenfullyexplored.

Anotherareaforinvestigationistheinfluenceofsurfacetreatmentandcoatingonthecorrosionresistanceandcrashworthinessofmagnesiumalloytubes.Whilemagnesiumhasahighstrength-to-weightratioandgooddampingcapacity,itisalsopronetocorrosioninhumidorsaltyenvironments.Therefore,varioustechniquessuchasanodizing,conversioncoating,orelectrolessplatinghavebeenappliedtoimprovethesurfaceprotectionandadhesionofmagnesiumalloys.However,itisunclearhowthesetreatmentsaffectthedeformationbehaviorandenergyabsorptionofthetubes,especiallyunderdynamicloadingconditions.

Furthermore,thecurrentstudyfocusedonquasi-staticdeformationtests,whichsimulatesloworstaticloadingconditions.However,inreal-worldcrashscenarios,theloadingratecanbemuchhigher,andthedeformationmechanismmaydifferduetostrainratesensitivityandthermalsoftening.Therefore,itwouldbeinterestingtoinvestigatethedynamicbehaviorandenergyabsorptioncharacteristicsofmagnesiumalloythin-walledtubesunderimpactorcrashtests,usingtechniquessuchasdropweight,compression,orcrashboxes.Suchexperimentscanalsoprovidevaluabledatafornumericalsimulationsandoptimizationofenergyabsorptionstructures.

Finally,thestudymainlyusedonetypeofmagnesiumalloy(AZ31B-O)withdifferentwallthicknessanddiameterratios.However,therearemanyothertypesandcompositionsofmagnesiumalloyswithvaryingmechanicalpropertiesandprocessingrequirements,dependingontheapplicationandenvironment.Therefore,acomparativestudyamongdifferentmagnesiumalloys,orbetweenmagnesiumalloysandotherlightweightmetalalloyssuchasaluminumortitanium,canprovideinsi