Inhloso esemqoka ye-PCB Baking ukuqeda amandla nokususa umswakama oqukethwe kwi-PCB noma kumunwe kusuka ezweni langaphandle, ngoba ezinye izinto ezisetshenziswe kwi-PCB uqobo lwawo akha ama-molecule wamanzi kalula akha ama-molecule wamanzi kalula.
Ngaphezu kwalokho, ngemuva kokuthi i-PCB ikhiqizwe futhi ibekwe isikhathi esithile, kunethuba lokuthola umswakama emvelweni, futhi namanzi kungenye yababulali abaphambili be-PCB popcorn noma ukunxusa.
Ngoba lapho i-PCB ibekwa endaweni lapho izinga lokushisa lidlula i-100 ° C, njenge-Onive Oven, i-wave soldering noma i-hand leveling, amanzi azophenduka umthamo wawo.
Ukushisa okusheshayo kusetshenziswa ku-PCB, ngokushesha umphunga wamanzi uzokwandisa; Ukushisa okuphezulu, kukhula umthamo omkhulu womphunga wamanzi; Lapho umphunga wamanzi engenakuphunyuka kwi-PCB ngokushesha, kunethuba elihle lokwandisa i-PCB.
Ikakhulu, ukuqondiswa kwe-PCB yinto entekenteke kunazo zonke. Kwesinye isikhathi i-vias phakathi kwezendlalelo ze-PCB ingahle iphulwe, futhi kwesinye isikhathi kungadala ukwahlukana kwezendlalelo ze-PCB. Okubi kakhulu, ngisho nokubonakala kwe-PCB kuyabonakala. IPhento, ukuvuvukala, nokuqhuma;
Kwesinye isikhathi noma ngabe izinto ezingenhla zingabonakali ngaphandle kwe-PCB, empeleni zilimele ngaphakathi. Ngokuhamba kwesikhathi, kuzodala imisebenzi engazinzile yemikhiqizo kagesi, noma i-caf nezinye izinkinga, futhi ekugcineni ibangela ukwehluleka komkhiqizo.
Ukuhlaziywa kwembangela yangempela yokuqhuma kwe-PCB nezindlela zokuvimbela
Inqubo yokubhaka ye-PCB empeleni iyinkinga impela. Ngesikhathi sokubhaka, ukufakwa kwangempela kufanele kususwe ngaphambi kokuthi kufakwe kuhhavini, bese izinga lokushisa kufanele libe ngaphezulu kwe-100 ℃ lokubhaka, kepha izinga lokushisa akufanele libe phezulu kakhulu ukugwema isikhathi sokubhaka. Ukunwetshwa ngokweqile kokuphupha kwamanzi kuzoqhuma i-PCB.
Ngokuvamile, izinga lokushisa le-PCB embonini lisethwe kakhulu ku-120 ± 5 ° C ukuqinisekisa ukuthi umswakama ungaqedwa emzimbeni we-PCB ngaphambi kokuthi uthengiswe kulayini we-SMT kwisithando se-SMT.
Isikhathi sokubhaka siyahlukahluka ngobukhulu nosayizi we-PCB. Okokuncipha noma ama-PCBS amakhulu, kufanele ucindezele iBhodi ngento esindayo ngemuva kokubhaka. Lokhu ukunciphisa noma ukugwema i-PCB ukwenzeka okubuhlungu kwe-PCB egoba ukuphuma kwezimo ngenxa yokukhishwa kwengcindezi ngesikhathi sokupholisa ngemuva kokubhaka ngemuva kokubhaka ngemuva kokubhaka.
Ngoba uma i-PCB ikhubazekile futhi igobe, kuzoba khona, kuzoba nobukhulu obungalingani lapho ukuphrinta umthengisi ku-SMT, okuzokwenza inani elikhulu le-SMT, elizodala izisulu ezingenalutho zokuphindaphinda.
Ukuhlelwa kwesimo se-PCB ukubhaka
Njengamanje, imboni ngokuvamile ibeka imibandela nesikhathi sokubhaka kwe-PCB kanjena:
1. I-PCB ivalwe kahle kungakapheli izinyanga ezi-2 zosuku lokukhiqiza. Ngemuva kokuvula, kubekwa endaweni yokushisa kanye nomswakama elawulwa okulawulwayo (≦ 30 ℃ / 60% RH, ngokusho kwe-IPC-1601) isikhathi esingaphezu kwezinsuku ezi-5 ngaphambi kokuya ku-inthanethi. Bhaka ku-120 ± 5 ℃ ngehora eli-1.
2. I-PCB igcinwe izinyanga ezi-2-6 ngaphezulu kosuku lokukhiqiza, futhi kufanele ibhakwe ngo-120 ± 5 ℃ amahora angama-2 ngaphambi kokuya ku-inthanethi.
I-3. I-PCB igcinwe izinyanga eziyi-6 kuya kwezi-12 ngaphezulu kosuku lokukhiqiza, futhi kufanele ibhakwe ngo-120 ± 5 ° C amahora ama-4 ngaphambi kokuya ku-inthanethi.
I-4. I-PCB igcinwe izinyanga ezingaphezu kwezingu-12 ukusuka ngosuku lokukhiqiza, ngokuyisisekelo akunconywa, ngoba amandla ebhizinisi le-multilayer azokhula ngokuzayo, futhi inqubo yokukhiqiza enjengezingozi ezinjengezingozi ezinjengokudla okumpofu kwepuleti nokudla okumpofu kwethayela. Uma kufanele uyisebenzise, kunconywa ukuyibhaka ngo-120 ± 5 ° C amahora ayi-6. Ngaphambi kokukhiqizwa kwesisindo, okokuqala zama ukuphrinta izingcezu ezimbalwa zokunameka umthengisi we-solder futhi uqiniseke ukuthi ayikho inkinga yokuzenzela ngaphambi kokuqhubeka nokukhiqiza.
Esinye isizathu ukuthi akunconywa ukusebenzisa ama-PCB agcinwe isikhathi eside ngoba ukwelashwa kwawo okungaphezulu kuzohluleka kancane kancane ngokuhamba kwesikhathi. Ku-Enig, impilo yeshelufu yomkhakha iyinyanga eziyi-12. Ngemuva kwalokhu kukhawulelwa, kuya ngediphozi yegolide. Ubukhulu buxhomeke ekubumbeni. Uma ubukhulu buncanyana, ungqimba lwe-nickel lungavela kungqimba lwegolide ngenxa yokuphazamiseka no-oxidation, okuthinta ukwethembeka.
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