Kev tshuaj xyuas zoo, kev soj ntsuam ntxaws ntxaws ntawm yuav ua li cas tswj cov qauv thiab dezincification corrosion kev ua tau zoo ntawm cam khwb cia hlau tooj dag
Cam khwb cia hlau tooj dag alloy muaj cov khoom siv zoo thiab kev ua haujlwm zoo thiab yog siv dav hauv cov khoom siv tu cev, cov kav dej, cov twj paj nruag, hydraulic li qub, thiab lwm yam. muaj cov degassing thiab deoxidation los ntawm zinc, thiab lwm yam, vim lub fact tias tooj dag yooj yim tsim coarse columnar crystals thaum lub sij hawm solidification txheej txheem thiab cov qauv casting yog ntxhib, nws yog ib qho yooj yim rau cua sov tawg thaum lub sij hawm casting txheej txheem. Leakage thiab lwm yam tshwm sim tshwm sim thaum siv, uas cuam tshuam rau nws cov kev ua tau zoo. Kev kho kom zoo ntawm cov qauv ntawm cov cam khwb cia tooj dag yog ib txoj hauv kev zoo los txhim kho cov kub tawg tsis kam thiab ntom. Tam sim no, ntxiv refiners yog txoj hauv kev tseem ceeb los kho cov qauv ntawm cov tooj dag. Cov ntaub ntawv kawm txog cov txiaj ntsig ntawm boron ntawm cov qauv ua kom zoo nkauj ntawm txhuas tooj dag. Ntxiv boron tuaj yeem txhim kho cov qauv cam khwb cia ntawm txhuas tooj dag. Cov ntaub ntawv tseem kawm RE Nws tuaj yeem kho cov qauv cam khwb cia ntawm txhuas tooj dag. Muaj qee qhov kev tshawb fawb txog qhov cuam tshuam ntawm boron thiab lub ntiaj teb tsis tshua muaj nyob rau hauv cov qauv thiab dezincification kev ua tau zoo ntawm cam khwb cia txhuas tooj dag. Daim ntawv no kawm txog cov teebmeem ntawm lub ntiaj teb tsis tshua muaj thiab boron refinement kho ntawm cov qauv ua-cam khwb cia thiab dezincification corrosion zog ntawm cam khwb cia txhuas tooj dag.
1. Cov ntaub ntawv xeem thiab cov txheej txheem
Cov khoom siv xeem yog ZCuZn40Pb2 txhuas tooj dag, thiab nws cov tshuaj lom neeg muaj pes tsawg leeg (feem ntau) yog 36.4% Zn, 1.70% Pb, 0.62%, A1, thiab Cu tshuav nyiaj li cas. Tsis tshua muaj ntiaj teb nrog 10% RE. AI master alloy yog ntxiv, thiab boron ntxiv raws li Cu-4.68%B master alloy. Ib tug graphite crucible yog muab tso rau hauv ib tug zoo-hom kuj rauv rau alloy smelting. Cov txheej txheem smelting ntawm cov hlau lead tooj dag yog raws li nram no: tus nqi yog melted, thiab thaum kub nce mus txog 1030 degree, boron thiab tsawg lub ntiaj teb refiners yog ntxiv raws li kev siv lub tswb thawv txoj kev, tag nrho stirred, thiab tom qab 10 feeb ntawm tshav kub preservation. , lub pouring preheating kub yog 350 degree. Sab laug thiab txoj cai hlau hom kuaj rods thiab hlau hom round khob specimens. Cov hlau puag ncig lub khob qauv qauv yog qhov yooj yim tshaj plaws thiab ncaj qha txoj hauv kev rau cov tuam txhab casting tooj liab los xyuas seb cov txheej txheem ua kom zoo zoo los yog tsis zoo. Txoj kev tshwj xeeb yog ncuav ib lub khob khob coj mus kuaj, thiab tom qab solidification thiab crusting, sai sai ncuav tawm cov unsolidified tooj liab kua nyob rau hauv nruab nrab ntawm lub round khob qauv kom tau ib tug plhaub khob qauv nrog ib tug solidified crystal nto. Los ntawm kev soj ntsuam cov yam ntxwv morphological ntawm lub ntsej muag siv lead ua los txiav txim cov txiaj ntsig ntawm kev ua kom zoo. Dezincification xeem ntawm cam khwb cia hlau tooj dag: corrosive tov yog 1% CuCl2: kev daws, cov tshuaj kub yog (75 ± 10) degree, lub sij hawm corrosion yog 24 teev, tom qab corrosion tiav, tshem tawm, ntxuav thiab qhuav, txiav. cov qauv los ntawm qhov chaw, thiab npaj cov qauv kub Theem tau siv los soj ntsuam thiab ntsuas qhov tob ntawm corrosion dezincification siv lub tshuab tsom iav los tshawb txog cov txiaj ntsig ntawm kev kho kom zoo ntawm dezincification corrosion ntawm cam khwb cia tooj dag. Txais [PUS. Saib xyuas lub microstructure nyob rau hauv PME3 metallographic microscope. Cov tshuaj corrosive rau cov ntaub so ntswg yog 5 gFeCl 3+5 mlHCl +100 ml aqueous kua.
2. Cov txiaj ntsig thiab kev tshuaj xyuas
2.1 Cov nyhuv ntawm refiner rau cov qauv ntawm cov hlau lead
Daim duab 1 qhia txog cov qauv ntawm cov hlau lead uas tsis muaj kev kho kom zoo thiab nrog boron thiab tsis tshua muaj lub ntiaj teb refinement. Nws tuaj yeem pom tau tias cov qauv ntawm cov hlau tsis huv pwm cam khwb cia txhuas tooj dag yog qhov ntxhib heev (Daim duab la). Raws li daim duab kos duab ntawm tooj liab-zinc theem, cov qauv cam khwb cia yuav tsum yog theem (dawb) + theem (dub) + Pb theem, Pb theem yog faib rau theem lossis nruab nrab ntawm theem thiab theem me me dub yooj yim hais. Cov thiab theem nyob rau hauv as-cast unrefined qauv yog faib nyob rau hauv tuab ntev laths. Tom qab kev kho RE thiab B kho kom zoo, cov theem thiab theem tau ua kom zoo dua qub. Tom qab kev kho B refinement, cov coarse lath-zoo li thiab theem tau ploj mus thiab hloov mus rau hauv luv luv flaky lossis equiaxed nplej (Daim duab 1b). Piv nrog rau cov qauv ua-cam khwb cia (Daim duab 1c), cov qauv ntawm cov tshuaj kho cov qauv yog qhov ua kom zoo dua qub, thiab cov theem hloov ntawm tuab ntev laths rau luv nyias laths. Yog li ntawd, rau cam khwb cia tooj dag alloys, RE thiab B refinement kev kho mob tuaj yeem txhim kho cov qauv ntawm cov cam khwb cia hlau. Nyob rau hauv qhov kev sim no, cov qauv kev ua kom zoo ntawm cov hlau lead tooj dag kho nrog boron yog qhov zoo dua li cov cam khwb cia tooj dag kho nrog boron. Cov nyhuv ntawm qhov tsawg lub ntiaj teb refinement kho.
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2.2 Cov nyhuv ntawm refiner ntawm qhov chaw morphology thiab cov qauv ntawm lub plhaub khob qauv
Daim duab 2 yog lub morphology ntawm cov siv lead ua nto ntawm lub plhaub khob qauv ua ntej thiab tom qab boron refinement kho cov kua tooj liab nyob rau hauv tib lub cub tawg. Nws tuaj yeem pom tau tias qhov saum npoo ntawm lub plhaub khob qauv cam khwb cia los ntawm unrefined tooj liab kua yog ntxhib (Daim duab 2a). Los ntawm kev pom macro, nws tuaj yeem pom tias muaj ntau qhov tsis sib xws me me ntawm lub ntsej muag siv lead ua. Daim duab 3a qhia txog cov khoom siv lead ua tsis zoo thiab nws qhov chaw nyob ib puag ncig. Los ntawm cov qauv morphology, nws tuaj yeem pom tias cov qauv ntawm qhov ntxhib saum npoo yog coarse columnar crystals, thiab cov ntxhib me me protrusions yog cov columnar dendrites sab laug ntawm cov kua / khoom sib txuas thaum cov kua tooj liab solidifies. Vim hais tias cov kua ntawm cov unsolidified dendrites tau nchuav thaum lub sij hawm kuaj, tawm, yog li cov columnar crystals tsim nyob rau hauv pem hauv ntej nyob rau hauv cov kua yog kiag li khaws cia, tsim ib tug ntxhib nto. Daim duab 2b yog qhov saum npoo ntawm boron-refined plhaub khob qauv. Piv nrog rau qhov tsis zoo, qhov saum npoo yog du thiab tsis muaj qhov ntxhib thiab pob me me. Qhov chaw kho qhov muag tsom iav qauv yog pom nyob rau hauv daim duab 3b. Crystal nto tsis sib xws, tab sis lub ntsej muag siv lead ua yog du. Cov qauv ntawm cov siv lead ua du nto qhia tau hais tias equiaxed crystallization, yog li kev kho kom zoo tuaj yeem hloov kho cov qauv ntawm cov hlau lead cam khwb cia.
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2.3 Cov txiaj ntsig ntawm kev kho kom zoo rau kev ua haujlwm dezincification ntawm cam khwb cia tooj dag
Daim duab 4 qhia txog cov txiaj ntsig ntawm kev kho kom zoo ntawm qhov dezincification qhov tob ntawm cam khwb cia tooj dag. Vim yog dezincification corrosion, cov qauv saum npoo yog txawv ntawm txheej dawb sab hauv. Qhov no yog vim hais tias nyob rau hauv ib puag ncig corrosive, zinc nyob rau saum npoo corrode, qhov concentration txo, zinc-nplua nuj theem (theem) nyob rau hauv cov qauv txo, thiab theem nce, uas ua rau ib tug pom tseeb qauv. sib txawv. Lub dezincification qhov tob ntawm unrefined tooj dag yog qhov loj (Daim duab 4a). Qhov nruab nrab qhov tob ntawm dezincification txheej ntawm cov hlau lead tooj dag yog 17000um, ua raws li kev ntsuas ntau ntawm cov txheej dezincification. Qhov tob ntawm dezincification txheej ntawm lub ntiaj teb tsis tshua muaj kev kho kom zoo yog qhov thib ob (Daim duab 4b). Qhov nruab nrab qhov tob ntawm zinc txheej yog 132.2um. Qhov tob ntawm dezincification txheej kho nrog boron refinement yog qhov tsawg tshaj plaws (Daim duab 4c). Qhov nruab nrab qhov tob ntawm txheej dezincification tsuas yog 57.2um los ntawm kev ntsuas ntau. Qhov no qhia tau hais tias kev kho kom zoo tuaj yeem tiv thaiv qhov dezincification corrosion ntawm cam khwb cia tooj dag thaum refining lub as-cast qauv. Hauv particular, cov nyhuv ntawm boron refinement kho ntawm inhibiting dezincification corrosion ntawm cam khwb cia tooj dag yog pom tseeb dua. Hais txog lub mechanism ntawm dezincification corrosion ntawm txhuas tooj dag, tam sim no muaj ob lub ntsiab mechanisms: ib qho yog dissolution. Cov kev hloov pauv hloov pauv thiab qhov kev nyiam tshaj plaws ntawm kev sib cais ntawm zinc tej zaum yuav yog qhov tshwm sim ntawm kev sib koom ua ke ntawm ob. Qhov kev nyiam tshaj plaws ntawm kev sib cais ntawm zinc ntseeg tau hais tias thaum lub sij hawm corrosion txheej txheem ntawm tooj dag, zinc nyob rau hauv lub alloy nto yog nyiam dua yaj los ntawm tooj dag, ua kom muaj ob qhov chaw ua haujlwm. Ob chav vacancy diffuse mus rau sab hauv ntawm alloy, thiab zinc alloy Cheebtsam diffuse rau saum npoo kom txog thaum yaj. Dissolve. Txoj kev kho dua tshiab ntseeg tias tooj dag dezincification corrosion suav nrog ob txoj hauv kev: ib qho yog tooj liab thiab zinc yaj ntawm lub anode tib lub sijhawm. Thaum cov tooj liab ions nyob rau hauv cov kev daws mus txog ib qho concentration, cov tooj liab ions raug txo kom nws yog xim hlau tooj liab thiab tso rau ntawm qhov chaw. , raws li ib tug ntxiv cathode kom ceev lub dissolution ntawm zinc nyob rau hauv lub alloy; Lwm qhov yog tias nyob rau lub sijhawm luv luv ntawm lub sijhawm pib, zinc nyiam dua yaj mus rau hauv cov tshuaj. Raws li zinc diffusion ua nyuaj, tooj liab thiab zinc yuav yaj nyob rau tib lub sij hawm, nrog rau cov rov qab-deposition ntawm tooj liab. . Boron refinement kev kho mob tuaj yeem cuam tshuam qhov dezincification ntawm tooj dag, feem ntau vim hais tias boron ntxiv rau ZCuZn40Pb2 txhuas tooj dag, uas tuaj yeem sau cov ciam teb thiab ob qhov chaw ua haujlwm, ua kom muaj kev sib raug zoo ntawm qhov ntawd, thiab cuam tshuam kev tsiv teb tsaws ntawm cov ciam teb thiab ob qhov chaw ua haujlwm. channel, txo cov kev tsiv teb tsaws ceev ntawm zinc, yog li txo qhov corrosion ntawm ZCuzn40Pb2 txhuas txhuas. RE kev kho kom zoo tuaj yeem tshem tawm cov impurities hauv cov tooj dag matrix. Thaum ZCuZn40Pb2 txhuas tooj dag muaj impurity hais xws li O thiab S, electrode muaj peev xwm sib txawv ntawm lawv thiab cov matrix yog loj, tsim ib tug thawj roj teeb thiab accelerating corrosion. Lub ntiaj teb tsis tshua muaj peev xwm cuam tshuam nrog O, S thiab lwm yam impurity. S generates siab melting point, tsawg ntom tsis tshua muaj lub ntiaj teb tebchaw [81], uas yooj yim ntab rau hauv lub slag, li no purifying lub matrix thiab txo tus nqi corrosion. Thaum lub ntiaj teb tsis tshua muaj ntxiv rau tooj dag, ib txheej nyias nyias thiab ntom ntom ntawm lub ntiaj teb tsis tshua muaj oxides yuav tsim rau ntawm qhov chaw. Nws tuaj yeem tiv thaiv qhov diffusion ntawm Zn thiab Cu atoms rau hauv cov tshuaj, txo qhov kev tawg, yog li ncua kev xeb thiab txhim kho dezincification corrosion kev ua haujlwm ntawm cov hlau.
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3. Cov lus xaus
(1) RE lossis B refinement kho tuaj yeem kho cov qauv zoo li ZCuZn40Pb2. Kev kho kom zoo tuaj yeem hloov qhov tuab ntev lath qauv ntawm tooj dag rau hauv luv luv laths lossis equiaxed siv lead ua qauv. Cov nyhuv refining ntawm B refining kev kho mob yog zoo dua li qhov uas tsis tshua muaj lub ntiaj teb refining kho. Kev kho kom zoo tuaj yeem hloov qhov chaw ntawm lub plhaub khob qauv los ntawm ntxhib mus rau du. Cov txheej txheej txheej ntxhib yog columnar siv lead ua, thiab cov txheej txheem du nto yog equiaxed crystals.
(2) RE los yog B refinement kev kho mob ntawm ZCuZn40Pb2 alloy yuav inhibit dezincification corrosion ntawm cam khwb cia tooj dag. Lub dezincification inhibition kev ua tau zoo ntawm B refinement kho yog pom tseeb dua li ntawm RE refinement kho.
