Inhloso esemqoka ye-PCB Baking ukwehlisa amandla futhi isuse umswakama, futhi ususe umswakama oqukethwe ku-PCB noma ungeniswe ngaphandle, ngoba ezinye izinto ezisetshenziswe ku-PCB uqobo lwazi kalula ama-molecule wamanzi.
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.
Lapho ijubane lokushisa i-PCB lishesha, umphunga wamanzi uzokhula ngokushesha; Lapho izinga lokushisa liphakeme, umthamo wevolumu yamanzi uzoba mkhulu; 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. I-Penomenon enjenge-blaiteling, ukuvuvukala kanye 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.
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 igcinwa izinyanga ezingaphezu kwezingu-12 ukusuka ngosuku lokukhiqiza. Ngokuyisisekelo, akunconywa ukuyisebenzisa, ngoba amandla anamathela ebhodini le-multilayer azokhula ngokuhamba kwesikhathi, kanye nezinkinga zekhwalithi efana nemisebenzi yomkhiqizo engazinzile kungenzeka ngokuzayo, okuzokwandisa imakethe ukuze kulungiswe. Ngaphezu kwalokho, inqubo yokukhiqiza ibuye ibe nezingozi ezinjengokuqhuma kwepuleti kanye 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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