Ubaluleke kangakanani umthelela womswakama ku-PCBA?

I-PCB ngenxa yokunemba nokuqina kwayo, izidingo zempilo yezemvelo kuwo wonke ama-workshop we-PCB ziphezulu kakhulu, futhi ezinye izinkundla zokuxhumana zivezwa “nokukhanya okuphuzi” usuku lonke. Umswakama, futhi ungenye yezinkomba ezidinga ukulawulwa ngokuqinile, namuhla sizokhuluma ngomthelela womswakama ku-PCBA.

“Umswakama” obalulekile

Umswakama uyinkomba ebaluleke kakhulu futhi elawulwa ngokuqinile enqubweni yokukhiqiza. Umswakama ophansi ungase ubangele ukoma, ukwanda kwe-ESD, ukukhuphuka kwamazinga othuli, ukuvaleka kalula kokuvuleka kwezifanekiso, nokwenyuka kokugqoka kwesifanekiso. Ukuzijwayeza kufakazele ukuthi umswakama ophansi uzothinta ngqo futhi unciphise umthamo wokukhiqiza. Ukuphakama kakhulu kuzodala ukuthi okokusebenza kudonse umswakama, okuholela e-delamination, imiphumela ye-popcorn, namabhola e-solder. Umswakama ubuye wehlise inani le-TG lezinto ezibonakalayo futhi ukhuphule i-warping eguqukayo ngesikhathi sokushisela.

Isingeniso kumswakama ongaphezulu

Cishe zonke izindawo eziqinile (njengensimbi, ingilazi, izitsha zobumba, i-silicon, njll.) zinongqimba olumanzi olumunca amanzi (ungqimba olulodwa noma lwamamolekyuli amaningi) olubonakala lapho izinga lokushisa elingaphezulu lilingana nezinga lokushisa lezinga lamazolo lomoya ozungezile ( kuye ngezinga lokushisa, umswakama, nomfutho womoya). Ukungqubuzana phakathi kwensimbi nensimbi kuyenyuka ngokuncipha komswakamo, futhi kumswakama olinganiselwe ongu-20% RH nangaphansi, ukungqubuzana kuphakeme ngokuphindwe izikhathi ezingu-1.5 kunomswakama ohlobene ongu-80% RH.

Izindawo ezimunca izimbotshana noma umswakama (ama-epoxy resins, amapulasitiki, ama-fluxes, njll.) zivame ukumunca lezi zingqimba ezimuncayo, futhi ngisho nalapho izinga lokushisa elingaphezulu lingaphansi kwendawo yamazolo (ukufingqa), ungqimba olumuncayo oluqukethe amanzi alubonakali ebusweni impahla.

Ngamanzi asezingqimbeni ezimunca i-molecule eyodwa kulezi zindawo angena ku-plastic encapsulation device (MSD), futhi lapho izendlalelo ezimunca i-molecule eyodwa zisondela ezingqimbeni ezingu-20 ngogqinsi, umswakama omuncwa yilezi zingqimba ze-molecule eyodwa ekugcineni. kubangela umphumela we-popcorn ngesikhathi sokuphinda kufakwe i-soldering.

Umthelela womswakama ngesikhathi sokukhiqiza

Umswakamo unemiphumela eminingi ekukhiqizeni nasekukhiqizeni. Ngokuvamile, umswakama awubonakali (ngaphandle kwesisindo esikhulayo), kodwa imiphumela iyizimbotshana, ama-voids, i-solder spatter, amabhola e-solder, nama-voids angaphansi.

Kunoma iyiphi inqubo, ukulawulwa komswakama nomswakama kubaluleke kakhulu, uma ukubonakala kwendawo yomzimba kungavamile, umkhiqizo ophelile awufaneleki. Ngakho-ke, i-workshop evamile kufanele iqinisekise ukuthi umswakama kanye nomswakama we-substrate surface kulawulwa kahle ukuze kuqinisekiswe ukuthi izinkomba zemvelo ohlelweni lokukhiqiza umkhiqizo oqediwe zingaphakathi kwebanga elishiwo.