Ephrintiwe wesifunda ibhodi ngemuva kokushisela kabusha kwe-reflow kuthanda ukugoba ipuleti okugoba, amagama abucayi azodala izingxenye zokushisela okungenalutho, isikhumbuzo nokunye, ungakunqoba kanjani?

1. Harm of PCB wesifunda ibhodi ukusonteka

Emgqeni wokuzenzakalela wobuso othomathikhi, uma ibhodi lesifunda lingabushelelezi, lizodala ukuma okunganembile, izingxenye azikwazi ukufakwa noma ukugxunyekwa embobeni nakubekwe phezulu kwephedi lebhodi, futhi kuze kulimaze umshini wokufaka othomathikhi. Ibhodi lesifunda eligcwele izingxenye ligobile ngemuva kokushisela, futhi izinyawo zezinto kunzima ukusika kahle. Amabhodi awakwazi ukufakwa ku-chassis noma kusokhethi yomshini, ngakho-ke isitshalo somhlangano esihlangabezane nokuthambekela kwebhodi nakho kuyinkinga kakhulu. Njengamanje, ubuchwepheshe obukhuphuka ebusweni bukhula buqonde ngokunemba okuphezulu, isivinini esikhulu nesiqondiso esihlakaniphile, okubeka phambili izidingo eziphakeme zokubhodloka kwebhodi le-PCB njengekhaya lezinto ezahlukahlukene.

Izinga le-IPC lisho ngokukhethekile ukuthi ukusikeka okuphezulu okuvumelekile kungu-0.75% webhodi le-PCB elinedivayisi yokuphakama komhlaba kanye no-1.5% webhodi le-PCB ngaphandle kwensimbi yokukhwela ebusweni. Eqinisweni, ukuze kuhlangatshezwane nezidingo zokunemba okuphezulu nokufakwa kwejubane elikhulu, abanye abakhiqizi bokufakwa kwe-elekthronikhi banezidingo eziqinile zokuguquguquka.

Ibhodi le-PCB lakhiwe nge-foil yethusi, i-resin, indwangu yengilazi nezinye izinto, zonke ezinezakhiwo ezahlukahlukene zomzimba nezamakhemikhali. Ngemuva kokucindezelwa ndawonye, ​​izinsalela zokucindezela ezishisayo zizokwenzeka nakanjani, okuholele ekuguqulweni. Ngesikhathi esifanayo inqubo PCB ukucutshungulwa, ngokusebenzisa izinga lokushisa eliphezulu, ahlabayo mechanical, inqubo ezimanzi kanye nezinye inqubo, uyoveza ithonya elikhulu ipuleti ukusonteka, ngamafuphi kungabangela PCB ukusonteka kuyinkimbinkimbi, indlela ukunciphisa noma ukuqeda kubangelwe ngu impahla ehlukene impahla kanye ukucutshungulwa, ukusonteka abakhiqizi PCB enye yezinkinga eziyinkimbinkimbi kakhulu.

2. Imbangela ukuhlaziywa deformation

Ukusonteka kwebhodi le-PCB kudinga ukutadishwa kusuka kuzinto ezibonakalayo, isakhiwo, ukusatshalaliswa kwemifanekiso, inqubo yokucubungula nokunye. Leli phepha lizohlaziya liphinde lichaze izizathu ezahlukahlukene zokuthi kungenzeka kube nezindlela zokusonteka nezokwenza ngcono.

Indawo engalinganiyo yethusi ebhodini lesifunda izokwenza ukuthi ukugoba nokuphambana kwebhodi kube kubi kakhulu.

Emklamweni webhodi lesifunda jikelele unendawo enkulu yocezu lwethusi lokumisa, kwesinye isikhathi ungqimba lwe-Vcc luklame indawo enkulu yocwecwe lwethusi, lapho lezi zindawo ezinkulu ze-foil yethusi zingakwazi ukusatshalaliswa ngokulinganayo emabhodini wesifunda afanayo, kuzodala ukushisa okungalingani futhi isivinini sokupholisa, amabhodi wesifunda, kunjalo, nawo angashisa ama-bilges ancipha, Uma ukunwetshwa nokuncipha kungenzeki ngasikhathi sinye kubangelwe izingcindezi ezahlukahlukene kanye nokushiyeka, ngalesi sikhathi uma izinga lokushisa lebhodi selifinyelele umkhawulo ophezulu we-Tg value, ibhodi lizoqala ukuthamba, okuholele ekuguqulweni unomphela.

Amaphoyinti okuxhuma (ama-ViAs) wezendlalelo ebhodini anciphisa ukunwetshwa nokuncipha kwebhodi

Kulezi zinsuku, ibhodi lesifunda ikakhulukazi ibhodi le-multilayer, futhi kuzoba khona ama-rivet afana nephuzu lokuxhuma (i-VIAS) phakathi kongqimba nongqimba, iphoyinti lokuxhuma lihlukaniswe ngembobo, imbobo engaboni kanye nomgodi wokungcwatshwa, lapho kunendawo yokuxhuma khona ukunciphisa umkhawulo wokunwetshwa kwepuleti nokusikwa, kuzobangela ngokungaqondile ukugoba kwepuleti nokugoqeka kwepuleti.

Isisindo sebhodi lesifunda ngokwaso singadala ukuthi ibhodi ligwedle futhi likhubaze

Isithando somlilo jikelele sizosebenzisa iketanga ukushayela ibhodi lesifunda esithandweni sokushisela phambili, okungukuthi, lapho izinhlangothi zombili zebhodi lapho i-fulcrum yokuxhasa lonke ibhodi, uma ibhodi lingaphezulu kwezingxenye ezisindayo, noma ubukhulu be Ibhodi likhulu kakhulu, ngenxa yenani lalo futhi livela phakathi kwesimo sokudangala, okuholele ekugoqeni kwepuleti.

Ukujula kwe-V-cut kanye ne-strip yokuxhuma kuzothinta ukuguqulwa kwephaneli

Ngokuyinhloko, i-V-cut iyimbangela yokucekela phansi isakhiwo sebhodi, ngoba i-V-cut iwukusika imisele eshidini elikhulu lokuqala, ngakho-ke kulula ukukhubaza indawo ye-V-cut.

2.1 Ukuhlaziywa komthelela wezinto ezicindezelwe, izakhiwo kanye nemidwebo ekuguqukeni kwepuleti

Ibhodi le-PCB lenziwa ngokucindezela ibhodi lomgogodla, ishidi eliqinile futhi ifreyimu yangaphandle yethusi. Ibhodi lomgogodla nocwecwe lwethusi kuyashiswa futhi kukhubazeke ngesikhathi sokucindezela. Inani le-deformation lincike ku-coefficient of thermal extension (CTE) yezinto ezimbili.

I-coefficient yokwandiswa okushisayo (CTE) yocwecwe lwethusi imayelana

I-Z-cTe ye-sub-sub ejwayelekile ye-FR-4 endaweni ye-Tg iphuzu.

Ngaphezulu kwephuzu le-TG, ngu (250-350) x10-6, futhi i-x-cTE imvamisa ifana nocwecwe lwethusi ngenxa yobukhona bendwangu yengilazi.