Eyona njongo yokubhaka kwe-PCB kukukhupha amanzi kunye nokususa ukufuma, kunye nokususa ukufuma okukwi-PCB okanye ukufunxwa ngaphandle, kuba ezinye izinto ezisetyenziswa kwi-PCB ngokwayo zenza iimolekyuli zamanzi ngokulula.
Ukongeza, emva kokuba i-PCB iveliswe kwaye ibekwe ixesha elithile, kukho ithuba lokufunxa ukufuma kokusingqongileyo, kwaye amanzi ngomnye wababulali abaphambili be-PCB popcorn okanye i-delamination.
Ngenxa yokuba xa i-PCB ibekwe kwindawo apho ubushushu budlula i-100 ° C, njenge-oven ye-reflow, i-oven e-soldering, i-hot air leveling okanye i-soldering yesandla, amanzi aya kujika abe ngumphunga wamanzi aze andise ngokukhawuleza umthamo wawo.
Xa isantya sokufudumeza iPCB sikhawuleza, umphunga wamanzi uya kwanda ngokukhawuleza; xa iqondo lokushisa liphezulu, umthamo womphunga wamanzi uya kuba mkhulu; xa umphunga wamanzi ungenako ukubaleka kwi-PCB ngoko nangoko, kukho ithuba elihle lokwandisa iPCB.
Ngokukodwa, umkhombandlela we-Z wePCB lolona buthathaka. Ngamanye amaxesha i-vias phakathi kweemaleko ze-PCB inokuthi yaphuke, kwaye ngamanye amaxesha inokubangela ukwahlukana kweemaleko ze-PCB. Okubi ngakumbi, kwanenkangeleko yePCB inokubonwa. Iziganeko ezifana nokudumba, ukudumba, kunye nokudubula;
Ngamanye amaxesha nokuba ezi ziganeko zingasentla azibonakali ngaphandle kwe-PCB, ngokwenene yonzakele ngaphakathi. Ngokuhamba kwexesha, iya kubangela imisebenzi engazinzanga yeemveliso zombane, okanye i-CAF kunye nezinye iingxaki, kwaye ekugqibeleni ibangele ukusilela kwemveliso.
Uhlalutyo lweyona sizathu sokudubula kwe-PCB kunye namanyathelo okuthintela
Inkqubo yokubhaka ye-PCB ngokwenene iyinkathazo. Ngexesha lokubhaka, ukupakishwa kokuqala kufuneka kususwe ngaphambi kokuba kufakwe kwi-oven, kwaye ke iqondo lokushisa kufuneka libe ngaphezu kwe-100 ℃ yokubhaka, kodwa iqondo lokushisa akufanele libe phezulu kakhulu ukuphepha ixesha lokubhaka. Ukwandiswa okugqithisileyo komphunga wamanzi kuya kugqabhuza iPCB.
Ngokuqhelekileyo, iqondo lokushisa lokubhaka le-PCB kushishino lubekwe kakhulu kwi-120 ± 5 ° C ukuqinisekisa ukuba ukufuma kunokupheliswa ngokwenene kumzimba we-PCB ngaphambi kokuba kuthengiswe kumgca we-SMT kwisithando somlilo.
Ixesha lokubhaka liyahluka ngobukhulu kunye nobukhulu bePCB. KwiiPCB ezincinci okanye ezinkulu, kufuneka ucinezele ibhodi ngento enzima emva kokubhaka. Oku kukunciphisa okanye ukuphepha i-PCB Isehlo esibuhlungu sokugoba kwe-PCB ngenxa yokukhululwa koxinzelelo ngexesha lokupholisa emva kokubhaka.
Kuba xa i-PCB ikhubazekile kwaye igobile, kuya kubakho i-offset okanye ubukhulu obungalinganiyo xa uprinta i-solder paste kwi-SMT, eya kubangela inani elikhulu leesekethe ezimfutshane ze-solder okanye iziphene ezingenanto ze-solder ngexesha lokuhamba kwakhona okulandelayo.
Okwangoku, ishishini ngokubanzi libeka iimeko kunye nexesha lokubhaka kwePCB ngolu hlobo lulandelayo:
1. I-PCB itywinwe kakuhle kwiinyanga ezi-2 zomhla wokwenziwa. Emva kokukhutshwa, ibekwe kwindawo elawulwa yiqondo lokushisa kunye nomswakama (≦30℃/60%RH, ngokwe-IPC-1601) ngaphezu kweentsuku ze-5 ngaphambi kokungena kwi-intanethi. Bhaka nge-120±5℃ ngeyure enye.
2. I-PCB igcinwa iinyanga ezi-2-6 ngaphaya komhla wokwenziwa, kwaye kufuneka ibhakwe nge-120±5℃ iiyure ezi-2 phambi kokungena kwi-intanethi.
3. I-PCB igcinwa iinyanga ezi-6-12 ngaphaya komhla wokwenziwa, kwaye kufuneka ibhakwe kwi-120±5°C iiyure ezi-4 phambi kokungena kwi-intanethi.
4. I-PCB igcinwe ngaphezu kweenyanga ezili-12 ukusuka kumhla wokwenziwa. Ngokwenene, akukhuthazwa ukuyisebenzisa, kuba amandla okubambelela kwibhodi ye-multilayer iya kuguga ngokuhamba kwexesha, kwaye iingxaki zekhwalithi ezifana nemisebenzi engazinzanga yemveliso inokuthi yenzeke kwixesha elizayo, eliya kwandisa imarike yokulungiswa. Ukongeza, inkqubo yokuvelisa ikwanayo nemingcipheko efana nokuqhushumba kwepleyiti kunye nokutya kakubi kwetoti. Ukuba kufuneka uyisebenzise, kucetyiswa ukuba ubhake kwi-120±5 ° C ngeeyure ze-6. Ngaphambi kokuveliswa kobuninzi, zama kuqala ukuprinta amaqhekeza ambalwa e-solder paste kwaye uqinisekise ukuba akukho ngxaki ye-solderability phambi kokuqhubeka kwemveliso.
Esinye isizathu kukuba akukhuthazwa ukusebenzisa ii-PCB ezigcinwe ixesha elide ngenxa yokuba unyango lwazo olungaphezulu luya kusilela ngokuthe ngcembe ekuhambeni kwexesha. Kwi-ENIG, ubomi beshelufu boshishino ziinyanga ezili-12. Emva kwesi sihlandlo sexesha, kuxhomekeke kwidiphozithi yegolide. Ubunzima buxhomekeke kubukhulu. Ukuba ubukhulu buncinci, i-nickel layer ingabonakala kwi-gold layer ngenxa yokusabalalisa kunye nefom ye-oxidation, echaphazela ukuthembeka.
5. Zonke ii-PCB ezibhakiweyo mazisetyenziswe zingaphelanga iintsuku ezi-5, kwaye ii-PCB ezingalungiswanga mazibhakwe nge-120±5°C enye iyure enye phambi kokungena kwi-intanethi.