Cov khoom hnyav yog ib qho tseem ceeb ntawm electronics. Cov phom nyhav tsis yog ib txwm zoo rau cov khoom uas yuav ua rau muaj kev sib tsoo phem, sib txhuam pins, lossis tsis muaj sib koom ua ke. Kev daws teeb meem rau cov teeb meem ntxhua lub zom zaws yog kev siv tus neeg sawv cev ntawm lub cev thiab qhov kub zoo.
Dab tsi yog Flux?
Thaum lub plhaub ziab yaj thiab cov ntaub ntawv sib txuas ntawm ob qho chaw ntawm hlau, nws ua tau ib daim ntawv sib txuas ua ke los ntawm kev sib xyaw nrog lwm yam hlau. Ib daim ntawv cog lus zoo yuav tsum tau muaj ob yam, ib lub cav uas yog sib txuas nrog cov hlau uas sib raug zoo thiab cov hlau zoo, tsis muaj oxides, plua plav, thiab grime uas tiv thaiv kev sib raug zoo. Grime thiab plua plav tau yooj yim raug tshem tawm los ntawm kev tu los yog tiv thaiv nrog cov tswv yim zoo cia. Oxides, ntawm qhov tod tes xav tau lwm txoj hau kev.
Oxides daim ntawv yuav luag txhua yam hlau thaum oxygen reacts nrog cov hlau. Rau hlau, oxidation yog feem ntau hu ua xeb, tab sis nws tshwm sim rau tin, txhuas, tooj liab, nyiaj, thiab ze li txhua hlau siv hauv hluav taws xob. Oxides ua cov nyom ntau dhau los lossis tseem ua tsis tau, tiv thaiv kom tau ib qho kev sib txuas nrog cov tshuab hlau. Oxidisation tshwm sim txhua lub sijhawm, tab sis tshwm sim sai dua thaum sov dua, zoo li thaum fwj tshuaj Flux ntxuav cov hniav hlau thiab reacts nrog oxide txheej, tawm hauv cov hluav taws xob zoo rau qhov sib tsoo zoo. Flux nyob rau ntawm cov hlau thaum lub cev uas tiv thaiv cov oxides ntxiv los ntawm kev sib sau ua rau lub siab kub hnyiab. Raws li nrog cov laug, muaj ntau hom kab laug sab, txhua tus siv qhov tseem ceeb thiab qee yam kev txwv thiab.
Hom Flux
Rau ntau daim ntawv sau npe, cov dej muaj nyob rau hauv cov tub ntxhais ntawm txoj kab xauv yas yog txaus. Txawm li cas los xij, muaj ob peb daim ntawv sau npe uas muaj qhov tsis muaj mob zoo txaus, xws li saum toj roob hauv caug thiab cov thooj av. Hauv txhua kis, qhov zoo tshaj plaws flux los siv yog qhov qaub ncaug acidic (tsawg txhoj puab heev) uas yuav ua haujlwm rau oxide ntawm cov khoom thiab ua rau muaj kev sib cog zoo.
Rosin Flux
Qee qhov qub tshaj plaws uas siv cov flux siv tau yog los ntawm cov ntoo kua txig (refined thiab purified) hu ua rosin. Rosin flux tseem siv tau hnub no, tiam sis feem ntau yog qhov muab cov kua nplaum los ua kom zoo tshaj plaws, ua kom zoo, thiab yam ntxwv. Qhov zoo tshaj plaws flux yuav yooj yim, tshwj xeeb tshaj yog thaum kub, tshem oxides sai, thiab pab tshem tawm cov khoom txawv teb chaws tawm ntawm cov hlau ntawm lub cev. Rosin flux yog aciding thaum kua, tab sis thaum nws txias nws ua zog thiab inert. Txij li thaum rosin flux yog inert thaum ua tau zoo, nws tuaj yeem sab laug ntawm PCB tsis ua mob rau lub thooj li tshwj tsis yog tias Circuit Court yuav sov rau qhov chaw uas lub rosin ua kua thiab pib noj ntawm qhov kev sib txuas. Vim li no nws yog ib txoj cai zoo los rhuav tshem cov kab mob hauv rosin nyob ntawm PCB. Tsis tas li ntawd, yog hais tias yuav tsum muaj cov ntaub ntim quav los yog PCB tshuaj pleev ib ce tseem ceeb, yuav tsum tau muab tshem tawm qhov yuav tsum tau muab tshem tawm. Rosin flux yuav raug muab tshem tawm nrog cawv.
Organic Acid Flux
Ib qho ntawm cov fuxes siv ntau tshaj yog siv dej soluble organic acid (OA) flux. Hom qog no muaj zog hauv cov organic acid flux, xws li citric, lactic, thiab stearic acid ntawm lwm tus. Cov tsis muaj zog cov organic acids nrog rau cov kuab tshuaj xws li isopropyl cawv thiab dej. Organic acid fluxes muaj zog uas rosin fluxes thiab ntxuav cov oxides tawm sai dua. Txuas ntxiv, cov dej ua kua dej muaj zog ntawm cov organic acid tau tso cai rau PCB kom yoojyim ntxuav tau cov dej tsis tu ncua (tsuas tiv thaiv cov khoom uas tsis ntub!). Kev tu cov organic acid yuav tsum tau txhaj vim tias qhov seem yog hluav taws xob ua hluav taws xob thiab yuav cuam tshuam qhov kev khiav hauj lwm thiab kev ua haujlwm ntawm ib lub voj voog, yog tias tsis ua rau kev puas tsuaj yog hais tias lub voj voog khiav hauj lwm ua ntej ua qhov dej ntawm qhov seem ntxuav tawm.
Inorganic Acid Flux
Ib qho kev xaiv uas muaj cov organic flux inorganic flux, uas yog qhov sib txawv ntawm cov tshuaj muaj zog xws li hydrocloric acid, zinc chloride, thiab ammonium chloride. Cov dej hauv inorganic acid yog tsom ntau ntxiv rau cov hlau muaj zog xws li tooj liab, tooj dag, thiab hlau tsis huv. Cov dej hauv inorganic acid yuav tsum tau tu kom huv tom qab siv los tshem tag nrho cov khoom seem corrosive los ntawm cov chaw uas yuav ua rau tsis muaj zog los yog txov cov laug khawm yog tias tso rau hauv qhov chaw. Yuav tsum tsis siv cov inorganic acid flux rau kev sib txuas lus los yog hluav taws xob.
Cov Ntaus Phom
Cov pa luam yeeb thiab cov pa tawm thaum lub caij hnyav tsis zoo rau kev nqus pa. Nws muaj ntau lub tebchaw ntawm cov acids thiab lawv cov tshuaj tiv thaiv nrog cov txheej oxide. Feem ntau cov tshuaj xws li formaldehyde, toluene, alcohols, thiab cov pa phem yog nyob rau hauv cov pa taws. Cov pa taws no tuaj yeem ua rau mob ntsws asthma thiab ua kom muaj kev hnov mob ntxiv rau cov pa luam yeeb. Cancer thiab ua tau teeb meem ntawm cov pa luam yeeb hauv qab no muaj tsawg heev vim lub khob noom khawb rau ob peb zaug kub dua qhov kub npau npau ntawm qhov kub thiab kub ntawm lub kav tsuag. Qhov kev pheej hmoo loj tshaj plaws yog kev tuav ntawm lub kauj vev xaij nws tus kheej. Kev tu mob yuav tsum tau noj thaum siv lub cav fais fab, nrog rau kev txhim kho kev ntxuav tes thiab tsis txhob noj mov, haus dej haus cawv, thiab haus luam yeeb hauv cov chaw uas muaj kab laug los tiv thaiv kab laug sab nkag los ntawm lub cev.