Yog tias koj tau hnov ​​txog lo lus “Halogen dawb PCB”Thiab xav kawm ntxiv, koj tau los rau qhov yog lawm. Peb qhia zaj dab neeg tom qab daim ntawv tshaj tawm Circuit board no.

Tshawb nrhiav qhov tseeb txog halogens hauv PCBS, halogens feem ntau thiab cov tseev kom muaj rau lo lus “tsis muaj halogen”. Peb kuj tau saib qhov zoo ntawm tsis muaj halogen.

PCB tsis muaj halogen yog dab tsi?

Txhawm rau ua kom tau raws li qhov yuav tsum tau ua ntawm tsis muaj halogen PCB, pawg thawj coj yuav tsum tsis pub ntau tshaj ib qho ntawm halogens hauv ib feem ntawm ib lab (PPM).

Halogens hauv polychlorinated biphenyl

Halogens muaj ntau yam kev siv cuam tshuam nrog PCBS.

Tshuaj chlorine yog siv los ua cov nplaim hluav taws lossis tiv thaiv txheej rau polyvinyl chloride (PVC) xov hlau. Nws kuj tseem siv los ua cov kuab tshuaj rau kev txhim kho semiconductor lossis ntxuav lub tshuab computer.

Bromine tuaj yeem siv ua cov nplaim hluav taws kom tiv thaiv cov khoom siv hluav taws xob lossis ua kom tsis muaj menyuam.

Qib twg yog suav tias tsis muaj halogen?

International Electrochemistry Commission (IEC) teeb tsa tus qauv ntawm 1,500 PPM rau tag nrho cov ntsiab lus halogen los ntawm kev txwv kev siv halogen. Cov kev txwv rau tshuaj chlorine thiab bromine yog 900 PPM.

PPM txwv zoo ib yam yog tias koj ua raws li Kev Nyab Xeeb Cov Khoom Txwv (RoHS).

Thov nco ntsoov tias ntau yam qauv halogen muaj nyob hauv khw. Txij li cov khoom lag luam tsis muaj halogen tsis yog qhov yuav tsum tau ua raws txoj cai, qib uas tau tso cai los ntawm cov koom haum ywj pheej, xws li cov tuam txhab tsim khoom, yuav txawv.

Halogen-free board tsim

Txij ntawm no mus, peb yuav tsum nco ntsoov tias qhov tseeb tsis muaj halogen PCBS nyuaj nrhiav. Tej zaum yuav muaj qhov me me ntawm halogens ntawm cov phiajcim hauv Circuit Court, thiab cov sib txuas no tuaj yeem muab zais rau hauv qhov chaw tsis tau xav txog.

Cia peb piav qhia qee qhov piv txwv. Lub rooj tsav xwm ntsuab ntsuab tsis yog halogen-dawb tshwj tsis yog tias lub substrate ntsuab raug tshem tawm los ntawm cov yeeb yaj kiab.

Cov tshuaj epoxy uas pab tiv thaiv PCBS tuaj yeem muaj cov tshuaj chlorine. Halogens kuj tseem yuav raug muab zais rau hauv cov khoom xyaw xws li iav gels, ntub dej thiab ua kom cov tshuaj tua kab mob, thiab cov tshuaj txhawb nqa.

Koj kuj yuav tsum paub txog qhov muaj peev xwm ua tau ntawm kev siv cov khoom tsis muaj halogen. Piv txwv li, thaum tsis muaj halogens, qhov sib piv rau qhov sib piv tuaj yeem cuam tshuam, ua rau khawb.

Nco ntsoov tias cov teeb meem zoo li no tsis tas yuav kov yeej. Ib txoj hauv kev yooj yim kom tsis txhob khawb yog siv cov tshuaj tiv thaiv kab mob (tseem hu ua solder resist) los txheeb cov ntaub qhwv.

Nws yog ib qho tseem ceeb los koom tes nrog cov kws tsim khoom lag luam PCB kom paub meej txog cov ntsiab lus halogen hauv PCB. Txawm hais tias lawv tau lees paub, tsis yog txhua lub khw tam sim no muaj peev xwm los tsim cov laug cam no.

Txawm li cas los xij, tam sim no koj paub qhov twg halogens nyob thiab lawv yog dab tsi, koj tuaj yeem hais qhia qhov xav tau. Tej zaum koj yuav tsum tau ua haujlwm ze nrog cov chaw tsim khoom los txiav txim siab txoj hauv kev zoo tshaj plaws kom tsis txhob muaj teeb meem halogens.

Txawm hais tias tau txais 100% PCB tsis muaj halogen tuaj yeem yog qhov nyuaj, koj tseem tuaj yeem tsim cov PCB rau qib uas lees paub raws li IEC thiab RoHS cov cai.

Dab tsi yog halogens?

Halogens tsis yog lawv tus kheej tshuaj lossis tshuaj. Lub sij hawm txhais los ntawm Greek rau “tus neeg ua ntsev” thiab hais txog cov khoom sib cuam tshuam hauv cov lus teev tseg.

Cov no suav nrog tshuaj chlorine, bromine, iodine, fluorine thiab A – qee qhov uas koj yuav paub nrog. Qhov tseeb lom zem: Ua ke nrog sodium thiab halogens los ua ntsev! Ib qho ntxiv, txhua lub caij muaj cov yam ntxwv tshwj xeeb uas muaj txiaj ntsig zoo rau peb.

Iodine yog tshuaj tua kab mob ntau heev. Cov tshuaj fluoride xws li tshuaj fluoride tau ntxiv rau cov khoom siv hauv dej los txhawb kev noj qab haus huv, thiab lawv kuj muaj nyob hauv cov roj nplua nyeem thiab tub yees.

Tsis tshua muaj neeg tsawg, nws qhov xwm txheej tsis nkag siab, thiab Tennessee Tinge tseem tab tom kawm.

Cov tshuaj chlorine thiab bromine muaj nyob hauv txhua yam los ntawm cov tshuaj tua kab rau cov tshuaj tua kab thiab, tau kawg, PCBS.

Vim li cas tsim cov PCBS tsis muaj halogen?

Txawm hais tias halogens ua lub luag haujlwm tseem ceeb hauv PCB cov qauv, lawv muaj qhov tsis zoo uas nyuaj rau tsis quav ntsej: tshuaj lom. Yog lawm, cov tshuaj no yog cov nplaim hluav taws thiab cov tshuaj tua kab, tab sis lawv raug nqi ntau heev.

Cov tshuaj chlorine thiab bromine yog cov ua txhaum loj ntawm no. Raug rau ib yam ntawm cov tshuaj no tuaj yeem ua rau cov tsos mob ntawm kev tsis xis nyob, xws li xeev siab, hnoos, ua rau tawv nqaij thiab qhov muag tsis pom kev.

Kev tswj hwm PCBS uas muaj halogens tsis zoo li yuav ua rau muaj kev phom sij txaus ntshai. Tseem, yog tias PCB ntes hluav taws thiab tso pa taws, koj tuaj yeem cia siab tias cov kev phom sij no tsis zoo.

Yog tias chlorine tshwm sim los sib xyaw nrog cov pa roj carbon monoxide, nws tsim cov dioxins, uas ua rau tuag taus. Hmoov tsis zoo, vim muaj cov peev txheej tsawg muaj rau rov ua dua PCBS kom nyab xeeb, qee lub tebchaws zoo li ua rau pov tseg tsis zoo.

Yog li ntawd, pov tseg tsis raug ntawm PCBS nrog cov ntsiab lus muaj tshuaj chlorine ntau yog txaus ntshai rau cov tsiaj txhu. Kev hlawv cov cuab yeej no kom tshem tawm lawv (uas tshwm sim) tuaj yeem tso dioxins rau ib puag ncig.

Cov txiaj ntsig ntawm kev siv PCBS tsis muaj halogen

Tam sim no koj paub qhov tseeb, vim li cas siv PCB tsis muaj halogen?

Qhov txiaj ntsig tseem ceeb yog tias lawv tsis muaj tshuaj lom rau lwm txoj hauv kev rau halogen puv. Qhov tseem ceeb tshaj rau kev nyab xeeb ntawm koj, koj cov kws tshaj lij, thiab cov neeg uas yuav tuav cov laug cam yog txaus los txiav txim siab siv lub rooj tsavxwm.

Ib qho ntxiv, kev pheej hmoo ib puag ncig qis dua li cov cuab yeej siv uas muaj cov tshuaj lom ntau. Tshwj xeeb tshaj yog nyob rau thaj chaw uas tsis muaj kev coj ua PCB rov ua dua tshiab, tsis muaj cov ntsiab lus halogen ua kom pov tseg kom nyab xeeb.

Hauv lub hnub nyoog ntawm thev naus laus zis thev naus laus zis, qhov uas cov neeg siv khoom tau paub ntau ntxiv txog cov tshuaj lom hauv lawv cov khoom, cov ntawv thov yuav luag tsis muaj qhov txwv-qhov zoo tshaj, tsis muaj halogen rau cov khoom siv hluav taws xob hauv tsheb, xov tooj ntawm tes thiab lwm yam khoom siv uas peb ua nyob ze.

Tab sis txo cov tshuaj lom tsis yog qhov txiaj ntsig nkaus xwb: lawv kuj muaj qhov ua tau zoo dua. Cov PCBS no feem ntau tuaj yeem tiv taus qhov kub thiab txias, ua rau lawv zoo tshaj rau cov hlau tsis muaj cov hlau lead. Txij li cov hlau lead yog lwm qhov sib txuas uas feem ntau kev lag luam sim zam, koj tuaj yeem tua ob tug noog nrog pob zeb.

Halogen-free PCB rwb thaiv tsev yuav raug nqi thiab siv tau rau cov khoom siv hluav taws xob pov tseg. Thaum kawg, vim tias cov laug cam no xa qis qis dielectric tsis tu ncua, nws yooj yim dua los tuav lub teeb liab ncaj ncees.

Peb txhua tus yuav tsum siv zog txhawb kom paub txog kev txwv tsis pub muaj kev phom sij xws li PCBS. Txawm hais tias tsis muaj halogen-PCBS tseem tsis tau tswj hwm los ntawm txoj cai, kev siv zog tau ua los ntawm cov koom haum txhawj xeeb kom tshem tawm kev siv cov tshuaj sib xyaw ua rau muaj kev phom sij no.