Txhua tus neeg uas tau ua haujlwm hauv kev lag luam abrasives, refractories, lossis ceramics paub tiassilicon carbide ntsuabHmoov me me no nyuaj rau ua haujlwm nrog. Cov khoom siv no, nrog rau qhov nyuaj ze li ntawm pob zeb diamond thiab kev ua haujlwm thermal thiab hluav taws xob zoo heev, yog qhov tsim nyog rau kev sib tsoo precision, cov khoom siv refractories qib siab, thiab cov khoom siv ceramic tshwj xeeb. Txawm li cas los xij, tsuas yog xav txog nws qhov nyuaj tsis txaus los siv nws kom zoo - muaj ntau yam ntxiv rau cov hmoov ntsuab zoo li qub no dua li qhov muag pom. Qhov tseem ceeb nyob rau hauv "qhov loj me ntawm cov khoom me me."
Cov kws ua haujlwm txog cov khoom siv feem ntau hais tias, "Thaum soj ntsuam cov khoom siv, xub saib cov hmoov; thaum soj ntsuam cov hmoov, xub saib cov khoom me me." Qhov no yog qhov tseeb tiag. Qhov loj me ntawm cov hmoov silicon carbide ntsuab txiav txim siab seb nws puas yuav yog ib qho khoom muaj zog lossis yog ib qho teeb meem loj hauv cov ntawv thov tom qab. Niaj hnub no, peb yuav kawm txog yuav ua li cas tswj qhov loj me ntawm cov khoom me me no thiab cov teeb meem kev siv tshuab uas cuam tshuam nrog kev ua tiav qhov kev tswj hwm no.
I. "Kev Sib Tsoo" thiab "Kev Sib Cais": Ib qho "Kev Phais Mob" hauv Qib Micron
Yuav kom tau qhov zoo tagnrhohmoov silicon carbide ntsuab, thawj kauj ruam yog "rhuav tshem" cov pob zeb loj ntsuab silicon carbide. Qhov no tsis yooj yim li kev tsoo lawv nrog rauj, tab sis yog ib qho txheej txheem zoo heev uas xav tau kev ua kom raug heev.
Txoj kev siv feem ntau yog kev sib tsoo tshuab. Txawm hais tias nws zoo li ntxhib, nws yuav tsum tau tswj hwm zoo. Cov tshuab sib tsoo pob yog qhov "chaw cob qhia" feem ntau, tab sis kev siv cov pob hlau ib txwm tuaj yeem yooj yim ua rau muaj cov hlau tsis huv. Cov txheej txheem siab dua tam sim no siv cov ntaub ceramic thiab silicon carbide lossis zirconia sib tsoo pob kom ntseeg tau tias muaj kev huv. Kev sib tsoo pob ib leeg tsis txaus; kom tau txais cov hmoov me me thiab sib xws dua, tshwj xeeb tshaj yog nyob rau hauv qhov ntau ntawm sub-10 micrometer (µm), "air jet milling" siv. Cov txheej txheem no siv cov cua ceev ceev los ua rau cov khoom sib tsoo thiab sib txhuam, ua rau muaj kev ua qias tuaj tsawg kawg nkaus thiab qhov faib me me ntawm cov khoom me me. Kev sib tsoo ntub dej los ua si thaum xav tau cov hmoov zoo heev (piv txwv li, qis dua 1 µm). Nws zoo tiv thaiv cov hmoov sib sau ua ke, ua rau cov slurries nrog kev sib kis zoo dua.
Txawm li cas los xij, tsuas yog "kev tsoo" tsis txaus; lub hauv paus tseem ceeb tiag tiag yog nyob rau hauv "kev faib tawm." Cov hmoov uas tsim los ntawm kev tsoo yuav txawv ntawm qhov loj me, thiab peb lub hom phiaj yog xaiv tsuas yog qhov loj me uas xav tau. Qhov no zoo li xaiv tsuas yog cov xuab zeb uas muaj txoj kab uas hla ntawm 0.5 txog 0.6 millimeters los ntawm ib pawg xuab zeb. Cov tshuab faib tawm cua qhuav tam sim no yog siv dav tshaj plaws, siv lub zog centrifugal thiab aerodynamics los cais cov hmoov ntxhib thiab cov hmoov zoo nrog kev ua haujlwm siab thiab cov zis loj. Tab sis muaj ib qho teeb meem: thaum cov hmoov zoo txaus (piv txwv li, qis dua ob peb micrometers), cov hmoov feem ntau yuav sib sau ua ke vim yog lub zog van der Waals (agglomeration), ua rau nws nyuaj rau cov neeg faib tawm huab cua kom cais lawv raws li qhov loj me ntawm cov khoom me me. Hauv qhov no, kev faib tawm ntub dej (xws li kev faib tawm centrifugal sedimentation) qee zaum tuaj yeem pab tau, tab sis cov txheej txheem nyuaj thiab tus nqi nce ntxiv.
Yog li, koj pom, tag nrho cov txheej txheem tswj qhov loj ntawm cov khoom me me yog qhov sib ntaus sib tua tas li ntawm "kev sib tsoo" thiab "kev faib tawm." Kev sib tsoo lub hom phiaj rau cov khoom me me, tab sis cov khoom me me dhau yuav yooj yim sib sau ua ke, cuam tshuam kev faib tawm; kev faib tawm lub hom phiaj rau qhov tseeb dua, tab sis feem ntau muaj teeb meem nrog cov hmoov me me sib sau ua ke. Cov kws ua haujlwm siv sijhawm feem ntau los sib npaug cov kev xav tau sib txawv no.
II. "Cov Teeb Meem" thiab "Cov Kev Dais Teeb Meem": Cov pos thiab lub teeb ntawm txoj kev mus rau kev tswj qhov loj ntawm cov khoom me me
Kev tswj qhov loj ntawm cov hmoov silicon carbide ntsuab kom ntseeg tau tias muaj ntau yam ntxiv tshaj li kev tsoo thiab kev faib tawm xwb. Muaj ntau yam "kev cuam tshuam" tiag tiag sawv ntawm txoj kev, thiab yog tsis daws qhov teeb meem ntawd, kev tswj kom meej meej yuav tsis ua tau.
Qhov teeb meem thawj zaug yog qhov kev tawm tsam los ntawm "kev tawv."Ntsuab silicon carbideyog ib qho nyuaj heev, xav tau lub zog loj heev los tsoo, ua rau cov khoom siv hnav ntau heev. Thaum lub sijhawm sib tsoo zoo heev, qhov hnav ntawm cov khoom sib tsoo thiab cov ntaub thaiv ua rau muaj ntau yam tsis huv. Cov khoom tsis huv no sib xyaw rau hauv cov khoom, ua rau nws tsis huv. Tag nrho koj txoj haujlwm nyuaj los tswj qhov loj ntawm cov khoom yuav tsis muaj txiaj ntsig yog tias cov qib tsis huv siab dhau. Tam sim no, kev lag luam tab tom tsim cov khoom sib tsoo thiab cov ntaub thaiv uas tiv taus kev hnav ntau dua, thiab txhim kho cov qauv khoom siv, txhua yam los daws qhov teeb meem no.
Tus tsov thib ob yog "txoj cai ntawm kev nyiam" hauv lub ntiaj teb ntawm cov hmoov zoo - agglomeration. Cov khoom me me dua, qhov loj dua ntawm thaj chaw tshwj xeeb, thiab qhov siab dua ntawm lub zog ntawm qhov chaw; lawv ib txwm nyiam "ua ke ua ke." Qhov kev sib sau ua ke no tuaj yeem yog "kev sib sau ua ke mos mos" (tuav ua ke los ntawm cov zog intermolecular, xws li cov zog van der Waals, uas yooj yim tawg ua ke), lossis qhov "kev sib sau ua ke nyuaj" (qhov twg thaum lub sijhawm sib tsoo lossis calcination, cov khoom me me ntawm qhov chaw yaj ib nrab lossis dhau los ntawm cov tshuaj lom neeg, vuam lawv ua ke nruj nreem). Thaum cov agglomerates tsim, lawv ua txuj ua "cov khoom loj" hauv cov cuab yeej tshuaj xyuas qhov loj me ntawm cov khoom me me, ua rau koj qhov kev txiav txim siab yuam kev; hauv kev siv ua haujlwm, xws li hauv cov kua polishing, cov agglomerates no yog "cov neeg ua txhaum" uas khawb qhov chaw ua haujlwm. Kev daws teeb meem agglomeration yog qhov kev sib tw thoob ntiaj teb. Dhau li ntawm kev ntxiv cov khoom ntxiv thiab ua kom zoo dua cov txheej txheem thaum lub sijhawm sib tsoo, ib txoj hauv kev muaj zog dua yog hloov kho qhov chaw hmoov, muab nws "txheej" los txo cov zog ntawm qhov chaw thiab tiv thaiv nws kom tsis txhob xav "ua ke ua ke."
3. Tus tsov thib peb yog qhov tsis paub meej hauv "kev ntsuas."
Koj paub li cas tias qhov loj ntawm cov khoom me me uas koj tau tswj hwm yog qhov koj xav tias nws yog? Cov khoom me me ntsuas qhov loj me yog peb lub qhov muag, tab sis cov ntsiab cai ntsuas sib txawv (laser diffraction, sedimentation, kev tshuaj xyuas duab), thiab txawm tias cov txheej txheem sib txawv ntawm cov qauv sib txawv hauv tib lub hauv paus ntsiab lus, tuaj yeem ua rau muaj txiaj ntsig sib txawv. Qhov no yog qhov tseeb tshwj xeeb rau cov hmoov uas twb tau sib sau ua ke lawm; yog tias kev sib cais kom zoo tsis tau ua tiav ua ntej ntsuas (piv txwv li, ntxiv cov khoom sib cais, kev kho ultrasonic), cov ntaub ntawv tau txais yuav deb ntawm qhov xwm txheej tiag tiag. Yog tsis muaj kev ntsuas txhim khu kev qha, kev tswj hwm meej tsuas yog lus hais tsis muaj txiaj ntsig.
Txawm hais tias muaj cov teeb meem no los xij, kev lag luam tseem niaj hnub nrhiav kev daws teeb meem. Piv txwv li, kev ua kom zoo dua thiab kev txawj ntse ntawm tag nrho cov txheej txheem yog qhov sib txawv loj. Los ntawm cov khoom siv saib xyuas qhov loj me ntawm cov khoom me me hauv online, cov ntaub ntawv rov qab los ntawm lub sijhawm tiag tiag thiab kev hloov kho tsis siv neeg ntawm cov txheej txheem crushing thiab kev faib tawm ua rau muaj cov txheej txheem ruaj khov dua. Ntxiv mus, thev naus laus zis hloov kho qhov chaw tau txais kev saib xyuas ntau ntxiv, tsis yog "kev kho" tom qab qhov tseeb, tab sis koom ua ke rau hauv tag nrho cov txheej txheem npaj, tiv thaiv kev sib sau ua ke los ntawm qhov chaw thiab txhim kho qhov kev sib kis ntawm cov hmoov thiab nws qhov sib xws nrog lub kaw lus thov. III. Kev Hu Rau Cov Ntawv Thov: Qhov Loj ntawm Cov Khoom Me Me Ua Li Cas "Phau Ntawv Qhia Txog Tus Neeg Xav"?
Vim li cas ho mus ntev heev los tswj qhov loj ntawm cov khoom me me? Kev saib cov ntawv thov ua rau nws meej. Hauv kev sib tsoo thiab polishing precision, xws li polishing sapphire screens thiab silicon wafers, qhov faib ntawm cov khoom me me ntawm cov hmoov silicon carbide ntsuab yog "txoj kab cawm siav." Nws xav tau qhov faib ntawm cov khoom me me nqaim heev thiab sib npaug, tsis muaj "cov khoom loj heev" (tseem hu ua "cov khoom abrasive" lossis "cov khoom tua neeg"), txwv tsis pub ib qho khawb tob tuaj yeem ua rau tag nrho cov khoom kim heev puas tsuaj. Tib lub sijhawm, cov hmoov yuav tsum tsis muaj cov agglomerates tawv, txwv tsis pub qhov ua tau zoo polishing yuav qis, thiab qhov tiav ntawm qhov chaw yuav tsis txaus siab. Ntawm no, kev tswj qhov loj me ntawm cov khoom me me raug tswj hwm ntawm nanoscale.
Hauv cov ntaub ntawv refractory siab heev, xws li cov rooj tog ceramic kiln thiab cov ntaub pua plag kub siab, kev tswj qhov loj ntawm cov khoom me me tsom mus rau "kev faib tawm qhov loj ntawm cov khoom me me." Cov khoom me me thiab cov khoom me me raug sib xyaw ua ke hauv ib qho kev faib ua feem; cov khoom me me tsim cov qauv, thiab cov khoom me me sau cov qhov sib txawv. Qhov no tso cai rau kev sib xyaw ua ke ntawm qhov kub thiab txias, ua rau muaj kev tiv thaiv thermal zoo. Yog tias qhov kev faib tawm ntawm cov khoom me me tsis tsim nyog, cov khoom yuav muaj qhov thiab tsis ruaj khov, lossis tawg yooj yim thiab yooj yim tawg. Hauv thaj chaw ntawm cov khoom siv ceramic tshwj xeeb, xws li cov khoom siv ceramics tsis muaj zog thiab cov nplhaib sib khi uas tsis hnav, qhov loj ntawm cov hmoov me me cuam tshuam ncaj qha rau cov qauv me me thiab kev ua tau zoo kawg tom qab sintering. Cov hmoov zoo heev thiab sib xws muaj kev ua haujlwm sintering siab, tso cai rau cov khoom siv ceramics ntom ntom dua thiab cov nplej zoo dua ntawm qhov kub qis dua, yog li txhim kho lawv lub zog thiab kev tawv. Ntawm no, qhov loj ntawm cov khoom me me yog qhov zais cia rau "kev txhawb zog" cov khoom siv ceramic.