Ekucubunguleni i-PCBA, ikhwalithi yokushisela yebhodi lesifunda inomthelela omkhulu ekusebenzeni nasekubukeni kwebhodi lesifunda. Ngakho-ke, kubaluleke kakhulu ukulawula izinga lokushisela lebhodi lesifunda le-PCB.Ibhodi lesifunda le-PCBikhwalithi yokushisela ihlobene eduze nomklamo webhodi lesifunda, izinto zokucubungula, ubuchwepheshe be-welding nezinye izici.
一、 Ukwakhiwa kwebhodi lesifunda le-PCB
1. Idizayini yephedi
(1) Lapho uklama amaphedi ezingxenye ze-plug-in, usayizi wephedi kufanele uklanywe ngendlela efanele. Uma i-pad inkulu kakhulu, indawo yokusabalalisa i-solder inkulu, futhi amalunga akhiwe awagcwele. Ngakolunye uhlangothi, ukungezwani okungaphezulu kwe-foil yethusi ye-pad encane kuncane kakhulu, futhi amalunga e-solder akhiwe angama-solder angamanzisi. Igebe elihambisanayo phakathi kwembobo nengxenye yokuhola likhulu kakhulu futhi kulula ukubangela ukusoda okungamanga. Uma imbobo ingu-0.05 - 0.2mm ububanzi kunomthofu futhi ububanzi bephedi buphindwe izikhathi ezingu-2 - 2.5 endaweni yokuvula, kuyisimo esifanelekile sokushisela.
(2) Lapho uklama amaphedi ezingxenye ze-chip, la maphuzu alandelayo kufanele acatshangelwe: Ukuze kuqedwe “umphumela wethunzi” ngangokunokwenzeka, amatheminali noma izikhonkwane ze-SMD kufanele zibhekane nesiqondiso sokugeleza kwethini ukuze kube lula. ukuxhumana nokugeleza kwethini. Yehlisa i-solder engamanga kanye ne-solder engekho. Izingxenye ezincane akufanele zibekwe ngemva kwezingxenye ezinkulu ukuvimbela izingxenye ezinkulu ukuthi zingaphazamisi ukugeleza kwe-solder futhi zithintane namaphedi wezingxenye ezincane, okuholela ekuvuzeni kwe-solder.
2, PCB wesifunda ibhodi flatness control
I-Wave soldering inezidingo eziphezulu ekubangeni kwamabhodi aphrintiwe. Ngokuvamile, i-warpage idingeka ukuthi ibe ngaphansi kuka-0.5mm. Uma ingaphezu kuka-0.5mm, idinga ukwenziwa isicaba. Ikakhulukazi, ubukhulu bamanye amabhodi aphrintiwe cishe bu-1.5mm, futhi izidingo zabo ze-warpage ziphakeme. Uma kungenjalo, ikhwalithi yokushisela ayikwazi ukuqinisekiswa. Lezi zindaba ezilandelayo kufanele zinakwe:
(1) Gcina kahle amabhodi aphrintiwe kanye nezingxenye futhi unciphise isikhathi sokugcina ngangokunokwenzeka. Ngesikhathi sokushisela, i-foil yethusi kanye nengxenye yokuhola engenalo uthuli, amafutha, nama-oxides kuyasiza ekwakhekeni kwamalunga afanelekayo e-solder. Ngakho-ke, amabhodi aphrintiwe kanye nezingxenye kufanele kugcinwe endaweni eyomile. , endaweni ehlanzekile, futhi unciphise isikhathi sokugcina ngangokunokwenzeka.
(2) Kumabhodi aphrintiwe abekwe isikhathi eside, indawo engaphezulu ngokuvamile idinga ukuhlanzwa. Lokhu kungathuthukisa ukuthengiselana futhi kunciphise i-soldering engamanga kanye namabhuloho. Kumaphini wengxenye anezinga elithile le-oxidation yangaphezulu, indawo engaphezulu kufanele isuswe kuqala. ungqimba lwe-oxide.
二. Ukulawulwa kwekhwalithi yezinto zenqubo
Ku-wave soldering, izinto eziyinhloko zenqubo ezisetshenziswayo yilezi: i-flux ne-solder.
1. Ukusetshenziswa kwe-flux kungasusa ama-oxide ebusweni be-welding, kuvimbele ukuphinda kufakwe i-oxidation ye-solder kanye ne-welding surface ngesikhathi se-welding, kunciphise ukungezwani kwendawo ye-solder, futhi kusize ukudlulisa ukushisa endaweni ye-welding. I-Flux idlala indima ebalulekile ekulawuleni ikhwalithi yokushisela.
2. Ukulawulwa kwekhwalithi ye-solder
I-solder ye-tin-lead iyaqhubeka nokufaka i-oxidize emazingeni okushisa aphezulu (250 ° C), okubangela ukuthi okuqukethwe kwethini le-tin-lead ebhodweni kuqhubeke kwehle futhi kuphambuke endaweni ye-eutectic, okuholela ekungabini kwamanzi kanye nezinkinga zekhwalithi njengokuqhubekayo. i-solder, i-solder engenalutho, namandla ahlangene e-solder anganele. .
三、Ukulawulwa kwepharamitha yenqubo yokushisela
Ithonya lamapharamitha wenqubo ye-welding kukhwalithi ye-welding surface iyinkimbinkimbi.
Kunamaphuzu amaningana ayinhloko: 1. Ukulawulwa kokushisa okushisa. 2. Welding ithrekhi ukuthambekela angle. 3. Ukuphakama kwe-Wave crest. 4. Izinga lokushisa lokushisela.
Ukushisela kuyisinyathelo esibalulekile senqubo yokukhiqiza ibhodi lesifunda le-PCB. Ukuze kuqinisekiswe ikhwalithi ye-welding yebhodi lesifunda, umuntu kufanele abe nekhono ezindleleni zokulawula ikhwalithi kanye namakhono wokushisela.
