1、?献?,功?,?恕翼刀双篇认蕊恶?思?黑土艇悠黑?骤 之 黑徽?七?,、?。,?,。?七?,?且?。?八?,?,?,?,?,?、?,?!?!?一毛?仟?!?!#%&(一r aydif fr aetion.TheeoatingwasmainlyeomPris edof尽Phase一A llZM g17.T he eontinuousim mer siontestin3.5 wtPetneutralNaCIsolutionindicatedthat the sPeeimenw ithdif fusion eoatinghadbettereorrosion resistanCe eom-ParedW
2、lththebareA艺,I UalloySPe CIme n1 hePote ntlodyn amlcPola rlz atlo nme as u rementthedif fu sio neo atingeo uld fu netio nasa n ef f eetiVelyprote etiv elaye rtoredu eetheeo r ro sio nalloywhen e xPo sedto35wtPetNaCIsolution.KEYWORDS:AzgiD;Magnesiumalloy;Corrosion;Dif f usioncoatingindieatedthatrateo
3、fAZ91D1.IntroduetionTheappliea tionofmagnesiumalloysinv a riousen-gineeringf ieldshasinereasedsteadilyinreeentyearsbeeausemagnesiumalloysexhibitan就traetive eom-b ina tion oflowdensityandh i ghratio ofstrengthtoweight.However,thesealloysareveryr ea,etiveinna-七u r e,a ndtheo xidef ilmf ormedontheallo
4、ysnatu-rallyeouldnotProvldeenougnProtect10nL一 Inelrinsuf f ieienteorrosionresistaneehasbeenaseriouslim-itationtoawideraPPlieationinPraetiee.T Oen-ha neetheeorrosionresist初eea ndimProvethePaint-adhesionProPerties ofmagnesiumallo ys,t heeonven-tional现ethods are ehemie欲eonversiontre乱ments.T hewell一know
5、nandef f eetiveeon versionProeesstoalumin umdif f usioneoa ting.F urthermore,theeorro-sionbeha viourofthedif f usioneoa tingwasemPha-sizedinthisstudy.ProdueeaProteet ivela yeronthesurf aeeofm乏 lglle-siumalloys15ba s edo nt heimme r sio nofthealloysinab a the o ntainingehr oma te.Ho w ev e r,thec hro
6、matebatlz sarebeingProgressivelyrestrietedduetoi tshi ghto xiei ty.Thereeentresearc hesontheProteetionofmagnesiuma lloysar ef oeusedontheenvironmen tala ndheal七hf riendlyPro e esse s,andv ariousnovelPro-eessesa,它br o ugh tf orwa rd 4一8.Int he ory,theeor ro-sionresistaneeofr nag nesiumal loyseanbeir
7、nprov edbyr nodif ieat ionoftheireomposi tiona ndmiC rostruc-ture.APromisingmet hod15basedonthedif f usional loyingtheory,eorrosionProteetionbeingat tributedtothef orma tionofaeo就ingeomprisedof intermetal-l ie eompou nds,whic heannotonl yimprovetheeor-r osionresistanee,butalsopro videenoughadhesions
8、trengthandbettermec haniealpr operties.War lgsr es ea rehgr ouP歌temPtedtoProteet the租agn esiumal loyby pow derpaek a luminizedeo atingf ro现1999,however,theres ul tswerenotdesiredbeeausethemagnesiur nal loysareextremelyeasytobeo xidizedandtheir租elting pointtemPera tures are very IOw.T heref ore,inthi
9、sresea reh,dif f usione()atingteeh-niq uewasearriedoutonAZ91Dmagnesiuma lloysPe(二ime n sbye ombina t角nof magnetroll sPutteringdeposi tion andv aeu umann ea ling tof orman exPeetedtPh.D.,towhomeor re spondeneeshouldbeaddr ess ed,E一mai l:hwhuoyahoo.eom.2.Exp,erimen talReetangula rspeeime nswi ththesiz
10、eof1 5mm只10mmx3mr nwe r ee utf roms a nd一eastAZ91Dal loy.Thenomi:Lalehemiea leomposi t ionofthe威loy 15givenin工幻le1.Thes u rf ae e soft hesPe eime n swe r eme eha nie allyPolishedb yeme ryP子Pers uPto1000 grit七0e n surethesamero ug hn ess,f ollo wedbywashingwi thaeetoneinanultrasonieba th.Pla nemagnet
11、ronsput teringe卿ipmen t,modelofSBH一5115D,从:a su s ed七0eo ata luminumonAZ91 Dalloysubstrates,Bef oreSPutteringdePosi七 ion,thesPeeimenoweresandblastedtoimProvetheadhesionbe七 wee ntheAIeo atinga ndthe substra te.T he sPut-teringdePo si七 io nwas c o ndu etedf or1.5 hu nderthepower of15 0 0Wa nda rgo npr
12、essu re of 0.2 PaAv aeuumannealingtreatmentwasperf ormedinatubef urnaee.Theannea lingtreatmentwaseon-duetedat450oCf or2h.T Oev aluatethee旋etofthetreatment,ahydrogenevolutionratemethodwasusedtomeas uretheeor-rosionra teofthesPeeimensduringimmersiontesta t25士ZOCf or10 0 h.T he sc l lematied ia罗amofthe
13、 set-up 15 showninF ig.1a nditsPrinei p lewas explainedindeta ilinliterature【9.In addition,t hepoten tiody-na miePola riz就ionmea su remen tin3.5w t Petn eutralNaC Isolutionwas earriedout w ithathree一elee七rodee ell.The sPe eime nwa sweldedw itha eoP Perw ire a ndem bed!dedinePo xyr esin aswo rkele et
14、rodef or ele etro-ehemiealte sting,andtheworka rea15about1em2.ThePolarizationrangewasf rom一0.5Vto+0.5Vv stheoPeneire uit Pote狱ial,肌dther neasuremen twascom mencedata Scanningrate of0.25 m V/5a f tertheSystemreaehedasteadyst就e.Themierostrueture andeomPo sition ofthe annealtrea tedspeeimen swas eharae
15、terizedusingaPhilips-X L 30:eanningeleetronoieroseope(SEM)equip pedMa七e r.Sei.T eehn ol.,V OI.23No3,2007T able1Cheniiea leompositionsofthea s一ea stAZ91Dmagneoiumal lo y(inwtpet)二蓄护(工浇r一:;仲三-石r气 j声.,.一万吃含.二BU阳t te班B e a k eSe als ntFU n n elS Pe ei me nFig.1Sehematied ia罗amofthe set一upf ornie韶uremen七
16、of hyd logene v oluti onra tew ithene rg ydispe r siv eX一r盯speetroseopy(E DS)a nd苏r盯山价a ctom e饶rw ithCuKar耐ia tion.3.Results alldDiseussion3.1八五盯05亡ru e亡ur eF igu re2showsthesu rf ae ea ndtlieero ss一seetionmorPholog iesofthesPuttereda luminumeoatingonthesubstra teofAZ91Da lloy.Theeoa tingwa snoteon1Pa ct,a ndsomeh olesa ndin terst ic eseoexl s七ed inthedepo sited.aluoin umeoa ting,al thou沙the sput-tering Pa ra meterswere oPtimized.Thestructureo fthe eoatinga pPearedtobetyPiea leylinder erysta l.T
