1. I-SMT solder paste ithinta kanjani ikhwalithi ye-soldering?
Isilinganiso se-flux mass kanye nokwakheka kwezingxenye ze-solder paste flux:
(1) Izinto ezakha ifilimu: 2%~5%, ikakhulukazi i-rosin, nokuphuma kokunye, izinto zokwenziwa, ezisetshenziswa kakhulu i-rosin emhlophe ngamanzi.
(2) I-Activator: 0.05%~0.5%, izivuseleli ezivame ukusetshenziswa zihlanganisa ama-dicarboxylic acid, ama-carboxylic acid akhethekile, nosawoti we-organic halide.
(3) I-ejenti Thixotropic: 0.2% ~ 2%, ikhulisa i-viscosity futhi isebenza njengokumiswa.Ziningi izinto ezinjalo, okungcono amafutha e-castor, i-hydrogenated castor oil, i-ethylene glycol mono butylene, ne-carboxymethyl cellulose.
(4) I-solvent: 3% ~ 7%, izingxenye eziningi, ezinamaphoyinti ahlukene abilayo.
(5) Abanye: ama-surfactants, ama-coupling agents.
Umthelela wokubunjwa kwe-solder paste flux kukhwalithi ye-solder:
I-Tin bead splash, i-flux splash, i-ball book array (BGA) ingenalutho, ibhuloho, nokunye ukucubungula kwe-chip ye-SMT nokushisela okungekuhle kunobudlelwane obuhle nokwakheka kokunamathisela kwe-solder.Ukukhethwa kwe-solder paste kufanele kukhethwe ngokuvumelana nezici zenqubo yomhlangano webhodi lesifunda eliphrintiwe (PCBA).Ingxenye ye-solder powder inethonya elikhulu ekuthuthukiseni ukusebenza kwe-slump kanye ne-viscosity.Ukuphakama kokuqukethwe kwempushana ye-solder, kuncane ukuwohloka.Ngakho-ke, i-solder paste esetshenziselwa izingxenye ze-fine-pitch kufanele isebenzise i-88% ~ 92% ngaphezulu kokuqukethwe kwe-solder powder kokunamathisela kwe-solder.
1. I activator inquma solderability noma wettability of the solder unama.Ukuze kuzuzwe i-soldering enhle, kufanele kube ne-activator efanelekile ku-solder paste, ikakhulukazi esimweni sokudayiswa kwe-micro-pad, uma umsebenzi unganele, kungase kubangele isenzakalo sebhola lamagilebhisi kanye nokukhubazeka kwe-socket yebhola.
2. Izinto ezakha ifilimu zithinta ukulinganiswa kwamalunga e-solder kanye ne-viscosity kanye ne-viscosity ye-solder paste.
3. I-Flux isetshenziselwa kakhulu ukuncibilikisa izivuseleli, izinto ezakha ifilimu, ama-thixotropic agents, njll. I-flux in solder paste ngokuvamile yakhiwa izincibilikisi ezinamaphoyinti abilayo ahlukene.Inhloso yokusebenzisa izincibilikisi zamaphuzu aphezulu abilayo ukuvimbela i-solder ne-flux ukuthi ingachaphazeli ngesikhathi sokufakwa kabusha kwe-reflow soldering.
4. I-ejenti Thixotropic isetshenziselwa ukuthuthukisa ukusebenza kokuphrinta nokusebenza kwenqubo.
2. Yiziphi izici ezithinta ukusebenza kahle kokukhiqizwa kwe-SMT?
Umjikelezo wokubeka ubhekisela esikhathini esisithathayo ukuze ikhanda lokubeka imishini liqale ukubala lapho i-Feeder ithatha izingxenye, ngemva kokutholwa kwesithombe sezingxenye, i-cantilever iya endaweni ehambisanayo, i-eksisi yokusebenza ibeka izingxenye ebhodini le-PCB. , bese ibuyela endaweni yokondla i-Feeder.Kungumjikelezo wokubeka;isikhathi esisetshenziswa emjikelezweni wokubeka siphinde sibe yinani eliyisisekelo lepharamitha elithinta isivinini somshini wokubeka.Umjikelezo wokubekwa kwemishini yokubeka i-cantilever enesivinini esikhulu yezingxenye zokuqina kokumelana ngokuvamile ungaphakathi kwama-1.0s.Njengamanje, ukubekwa kwe-SMT Umjikelezo we-cantilever mounter yesivinini esiphezulu embonini yokucubungula ama-chip cishe u-0.5s;umjikelezo wokukhweza ama-IC amakhulu, ama-BGA, izixhumi, nama-aluminium electrolytic capacitor cishe ama-2s.
Izinto ezithinta umjikelezo wokubekwa:
Izinga lokuvumelanisa lokucosha izingxenye (okungukuthi, izinduku zokuxhuma eziningi zekhanda lokubeka ziyakhuphuka futhi ziwe ngesikhathi esisodwa ukuze kuthathwe izingxenye).
Usayizi webhodi le-PCB (ibhodi le-PCB elikhudlwana, i-X/Y enkulu yobubanzi bekhanda lokubeka, kanye nesikhathi sokusebenza eside).
Izinga lokujikijelwa kwengxenye (uma amapharamitha wengxenye yesithombe angasethiwe kahle, ukujikijelwa kwemishini nezenzo ze-X/Y ezingavumelekile zizokwenzeka phakathi nenqubo yokuqaphela isithombe yezingxenye zokumunca).
Idivayisi isetha inani lepharamitha yesivinini esinyakazayo X/Y/Z/R.
3. Ungagcina kanjani futhi usebenzise kanjani ukunamathisela kwe-solder embonini yokucubungula isichibi se-SMT?
1. Uma i-solder paste ingasetshenziswa, kufanele igcinwe esiqandisini, futhi izinga lokushisa layo lokugcina kufanele libe phakathi kwe-3 ~ 7 ° C.Sicela uqaphele ukuthi ukunamathisela kwe-solder akukwazi ukuqhwa ngaphansi kuka-0°C.
2. Kufanele kube ne-thermometer ezinikele esiqandisini ukuze ibone izinga lokushisa eligciniwe njalo emahoreni ayi-12 futhi wenze irekhodi.I-thermometer idinga ukuhlolwa njalo ukuvimbela ukwehluleka, futhi amarekhodi afanele kufanele enziwe.
3. Lapho uthenga i-solder paste, kuyadingeka ukunamathisela usuku lokuthenga ukuze uhlukanise amaqoqo ahlukene.Ngokusho kwe-SMT chip processing order, kuyadingeka ukulawula umjikelezo wokusetshenziswa kwe-solder paste, futhi i-inventory ngokuvamile ilawulwa phakathi kwezinsuku ezingu-30.
4. Isitoreji se-solder paste kufanele sigcinwe ngokuhlukana ngokwezinhlobo ezahlukene, izinombolo ze-batch, nabakhiqizi abahlukene.Ngemuva kokuthenga i-solder paste, kufanele igcinwe esiqandisini, futhi isimiso sokuqala sokungena, sokuqala kufanele silandelwe.
4. Yiziphi izizathu zokushisela okubandayo ekucubunguleni kwe-PCBA
1. Izinga lokushisa lokugeleza kabusha liphansi kakhulu noma isikhathi sokuhlala ekushiseni kwe-reflow soldering sifushane kakhulu, okuholela ekushiseni okunganele ngesikhathi sokugeleza kabusha kanye nokuncibilika okungaphelele kwempushana yensimbi.
2. Esigabeni sokupholisa, umoya opholile onamandla, noma ukunyakaza kwebhande lokudlulisa elingalingani kuphazamisa amalunga e-solder, futhi kuveza ubujamo obungalingani ebusweni bamalunga e-solder, ikakhulukazi ezingeni lokushisa elingaphansi kancane kunephuzu lokuncibilika, lapho i-solder ithambile kakhulu.
3. Ukungcola okungaphezulu naseduze namaphedi noma imikhondo kungavimbela amandla okuguquguquka, okuholela ekugelezeni kabusha okungaphelele.Ngezinye izikhathi i-solder powder engancibiliki ingabonwa ebusweni be-solder joint.Ngesikhathi esifanayo, umthamo we-flux onganele uzophinde ubangele ukukhishwa okungaphelele kwama-oxide ensimbi kanye nokufiphala okungaphelele okulandelayo.
4. Izinga le-solder metal powder alilungile;iningi lazo lakhiwe yi-encapsulation yezinhlayiya ze-powder ene-oxidized kakhulu.
5. Uyihlanza kanjani i-PCB Assembly ngendlela ephephile nephumelelayo kakhulu
Ukuhlanza imihlangano ye-PCB kufanele kusebenzise isihlanzi esifaneleka kakhulu nesincibilikisayo sokuhlanza, okuncike ezidingweni zebhodi.Lapha, izindlela ezihlukene zokuhlanza i-PCB kanye nobuhle nobubi bazo ziyaboniswa.
1. Ultrasonic PCB Cleaning
Isicoci se-PCB se-ultrasonic sihlanza ama-PCB angenalutho ngokushesha ngaphandle kokuhlanza i-solvent, futhi lena indlela yokuhlanza i-PCB eyonga kakhulu.Ngaphandle kwalokho, le ndlela yokuhlanza ayikhawuli usayizi we-PCB noma ubuningi.Nokho, ayikwazi ukuhlanza umhlangano we-PCB ngoba i-ultrasonic ingalimaza izingxenye ze-elekthronikhi kanye nokuhlanganisa.Futhi ayikwazi ukuhlanza i-aerospace/defense PCB ngoba i-ultrasonic ingathinta ukunemba kukagesi webhodi.
2. Ukuhlanza Okugcwele Okuzenzakalelayo kwe-PCBA ku-inthanethi
Isicoci esiphelele se-PCBA eku-inthanethi esizenzakalelayo sifanelekile ukuhlanza amavolumu amakhulu okuhlanganiswa kwe-PCB.Kokubili i-PCB ne-PCBA kungahlanzwa, futhi ngeke kuthinte ukunemba kwamabhodi.Ama-PCBA adlulisa imigodi ehlukene egcwele i-solvent ukuze aqedele izinqubo zokuhlanza okusekelwe emanzini ngamakhemikhali, ukuhlanza okusekelwe emanzini, ukomisa, nokunye.Le ndlela yokuhlanza ye-PCBA idinga ukuthi i-solvent ihambisane nezingxenye, i-PCB surface, imaski ye-solder, njll. Futhi kufanele sinake izingxenye ezikhethekile uma kwenzeka zingakwazi ukuwashwa.I-Aerospace kanye ne-PCB yebanga lezokwelapha ingahlanzwa ngale ndlela.
3. Ukuhlanza okuzenzakalelayo kwe-PCBA okuyingxenye
Ngokungafani nesicoci se-PCBA esiku-inthanethi, isicoci esizenzakalelayo singathuthwa ngesandla kunoma iyiphi indawo yomugqa wokuhlanganisa, futhi sinomgodi owodwa kuphela.Yize izinqubo zayo zokuhlanza zifana nokuhlanzwa kwe-PCBA eku-inthanethi, zonke izinqubo zenzeka endaweni efanayo.Ama-PCBA adinga ukulungiswa into ethile noma abekwe kubhasikidi, futhi ubuningi bawo bulinganiselwe.
4. PCBA Manuwali Cleaning
Isicoci se-PCBA semanuwali sifanele i-PCBA yenqwaba encane edinga isinyibilikisi sokuhlanza i-MPC.I-PCBA iqeda ukuhlanzwa okususelwe emanzini ngamakhemikhali endaweni yokugeza yokushisa engashintshi.
Sikhetha indlela yokuhlanza efaneleke kakhulu ye-PCBA kuye ngezidingo ze-PCBA.