Cholinga chachikulu cha PCB pamwamba mankhwala ndi kuonetsetsa weldability wabwino kapena katundu magetsi.Chifukwa mkuwa m'chilengedwe umakhalapo mu mawonekedwe a oxides mumlengalenga, sizingatheke kuti ukhalebe ngati mkuwa woyambirira kwa nthawi yaitali, choncho umayenera kuchitidwa ndi mkuwa.
Pali njira zambiri zamankhwala za PCB pamwamba.Zinthu wamba ndi lathyathyathya, organic welded protective agents (OSP), full -board faifi tambala -wokutidwa golide, Shen Jin, Shenxi, Shenyin, mankhwala faifi tambala, golide, ndi electroplating golide wolimba.Chizindikiro.
Njira yayikulu yowotchera mpweya wotentha ndi: kukokoloka kwakung'ono → kutenthetsa → kuwotcherera → kupopera malata → kuyeretsa.
Mpweya wotentha ndi wathyathyathya, womwe umadziwikanso kuti hot air welded (yomwe imadziwika kuti tin spray), yomwe ndi njira yopangira malata osungunuka (kutsogolera) omwe amawotchedwa pa PCB pamwamba ndikugwiritsa ntchito kutentha kukakamiza kuwongolera mpweya (kuwomba) kuti apange. wosanjikiza wa anti-copper oxidation.Itha kuperekanso zigawo zabwino zokutira weldability.The weld lonse ndi mkuwa wa mpweya wotentha kupanga mkuwa - malata zitsulo interductive pawiri pa osakaniza.PCB kawirikawiri kumira mu kusungunuka welded madzi;mphepo mpeni kuwombeza madzi welded lathyathyathya madzi welded pamaso welded;
Mlingo wa mphepo yotentha umagawidwa m'magulu awiri: ofukula ndi yopingasa.Ambiri amakhulupirira kuti yopingasa mtundu ndi bwino.Ndi yopingasa yopingasa yotentha mpweya rectification wosanjikiza ndi yunifolomu, amene angathe kukwaniritsa kupanga zokha.
Ubwino: nthawi yayitali yosungira;PCB ikamalizidwa, pamwamba pa mkuwa imakhala yonyowa kwambiri (malata amaphimbidwa kwathunthu asanawotchedwe);oyenera kuwotcherera kutsogolera;ndondomeko yokhwima, yotsika mtengo, yoyenera kuyang'anitsitsa maso ndi kuyesa magetsi
Kuipa: Osayenerera kumangirira mzere;chifukwa cha vuto la flatness pamwamba, palinso malire pa SMT;sikoyenera kulumikizana ndikusintha kapangidwe.Pamene kupopera mankhwala malata, mkuwa udzasungunuka, ndipo bolodi ndi kutentha kwambiri.Makamaka mbale zokhuthala kapena zoonda, kutsitsi kwa malata kumakhala kochepa, ndipo ntchito yopanga imakhala yovuta.
Njira yonseyi ndi: kutsitsa -> micro-etching -> pickling -> kuyeretsa madzi oyera -> zokutira organic -> kuyeretsa, ndikuwongolera njira ndikosavuta kuwonetsa njira yochizira.
OSP ndi njira yopangira chithandizo chamkuwa chamkuwa (PCB) potengera zofunikira za malangizo a RoHS.OSP ndi yachidule ya Organic Solderability Preservatives, yomwe imadziwikanso kuti organic solderability preservatives, yomwe imadziwikanso kuti Preflux mu Chingerezi.Mwachidule, OSP ndi filimu yapakhungu yopangidwa ndi mankhwala pamalo oyera, opanda mkuwa.Kanemayu ali odana ndi makutidwe ndi okosijeni, kutentha mantha, kukana chinyezi, kuteteza mkuwa pamwamba mu malo yachibadwa salinso dzimbiri (makutidwe ndi okosijeni kapena vulcanization, etc.);Komabe, mu kuwotcherera wotsatira kutentha kwakukulu, filimu yotetezera iyi iyenera kuchotsedwa mosavuta ndi kutuluka mofulumira, kuti poyera mkuwa woyera pamwamba ukhoza kuphatikizidwa nthawi yomweyo ndi solder yosungunuka mu nthawi yochepa kwambiri kuti ikhale yogwirizana ndi solder.
Ubwino: Njirayi ndi yosavuta, pamwamba pake ndi yathyathyathya kwambiri, yoyenera kuwotcherera opanda lead ndi SMT.Easy rework, yabwino kupanga ntchito, oyenera yopingasa mzere ntchito.Bolodi ndi yoyenera kukonzedwa kangapo (mwachitsanzo OSP+ENIG).Mtengo wotsika, wokonda zachilengedwe.
Zoipa: kuchepetsa chiwerengero cha kuwotcherera reflow (kuwotcherera angapo wandiweyani, filimuyo idzawonongedwa, makamaka 2 nthawi palibe vuto).Osayenera ukadaulo wa crimp, kumanga waya.Kuzindikira kowoneka ndi kuzindikira kwamagetsi sikoyenera.Chitetezo cha mpweya wa N2 ndichofunika pa SMT.Kukonzanso kwa SMT sikoyenera.Zofunika zosungirako zapamwamba.
Plate nickel plating ndi PCB pamwamba kondakitala choyamba yokutidwa ndi wosanjikiza faifi tambala kenako yokutidwa ndi wosanjikiza golide, faifi tambala plating makamaka kupewa kufalikira pakati golide ndi mkuwa.Pali mitundu iwiri ya golide wa nickel electroplated: golide wofewa (golide woyenga, pamwamba pa golide samawoneka wowala) ndi golide wolimba (wosalala ndi wolimba, wosavala, wokhala ndi zinthu zina monga cobalt, pamwamba pa golide amawoneka owala).Golide wofewa amagwiritsidwa ntchito makamaka pakuyika tchipisi waya wagolide;Golide wolimba amagwiritsidwa ntchito makamaka polumikizana ndi magetsi osamangika.
Ubwino: Nthawi yayitali yosungira> miyezi 12.Zoyenera kupanga ma switch switch komanso kumangirira waya wagolide.Oyenera kuyesa magetsi
Kufooka: Kukwera mtengo, golide wokhuthala.Zala zokhala ndi ma electroplated zimafunikira ma waya owonjezera opangira.Chifukwa makulidwe a golidi sagwirizana, akagwiritsidwa ntchito pa kuwotcherera, angayambitse kutsekemera kwa mgwirizano wa solder chifukwa cha golide wandiweyani, zomwe zimakhudza mphamvu.Vuto la electroplating surface uniformity.Golide wa nickel wopangidwa ndi electroplated samaphimba m'mphepete mwa waya.Sikoyenera kumangirira waya wa aluminiyamu.
Zomwe zimachitika nthawi zambiri ndi: pickling kuyeretsa -> micro-corrosion -> preleaching -> activation -> electroless nickel plating -> mankhwala golide leaching;Pali akasinja 6 amankhwala munjirayi, kuphatikiza mitundu pafupifupi 100 yamankhwala, ndipo njirayi ndi yovuta kwambiri.
Golide womira amakulungidwa muzitsulo zagolide za nickel zabwino kwambiri, zomwe zimatha kuteteza PCB kwa nthawi yaitali;Kuphatikiza apo, ilinso ndi kulekerera kwachilengedwe komwe njira zina zochizira pamwamba sizikhala nazo.Kuonjezera apo, kumiza golide kungalepheretsenso kusungunuka kwa mkuwa, zomwe zidzapindulitse msonkhano wopanda lead.
Ubwino: oxidize si kophweka, akhoza kusungidwa kwa nthawi yaitali, pamwamba ndi lathyathyathya, oyenera kuwotcherera zikhomo zabwino kusiyana ndi zigawo zikuluzikulu ndi mfundo zazing'ono solder.PCB board yomwe mumakonda yokhala ndi mabatani (monga bolodi la foni yam'manja).Reflow kuwotcherera kumatha kubwerezedwa kangapo popanda kutayika kwakukulu kwa kuwotcherera.Itha kugwiritsidwa ntchito ngati maziko a waya wa COB (Chip On Board).
Zoipa: kukwera mtengo, mphamvu zowotcherera zopanda mphamvu, chifukwa kugwiritsa ntchito njira yopanda mafuta ya nickel, yosavuta kukhala ndi mavuto a disk wakuda.Nickel layer imatulutsa okosijeni pakapita nthawi, ndipo kudalirika kwanthawi yayitali ndi vuto.
Popeza ma solders onse omwe alipo tsopano ali ndi malata, wosanjikiza wa malata amatha kufananizidwa ndi mtundu uliwonse wa solder.Njira yakumira malata imatha kupanga zitsulo zamkuwa zamkuwa zachitsulo, zomwe zimapangitsa malata omira kukhala ndi solderability wabwino wofanana ndi kutentha kwa mpweya wotentha popanda kupweteka kwamutu kwavuto lakuthwa kwa mpweya wotentha;Chipinda cha malata sichingasungidwe motalika kwambiri, ndipo msonkhanowo uyenera kuchitidwa molingana ndi dongosolo la malata omira.
Ubwino: Oyenera kupanga mizere yopingasa.Oyenera kukonza mzere wabwino, woyenera kuwotcherera wopanda lead, makamaka oyenera ukadaulo wa crimping.Kutsika kwabwino kwambiri, koyenera kwa SMT.
Kuipa: Malo abwino osungira amafunika, makamaka osapitirira miyezi 6, kuti muchepetse kukula kwa ndevu za malata.Sikoyenera kupanga masinthidwe olumikizirana.Popanga, filimu yokaniza kuwotcherera ndiyokwera kwambiri, apo ayi zipangitsa kuti filimu yokana kuwotcherera igwe.Pa kuwotcherera angapo, chitetezo cha gasi cha N2 ndichabwino kwambiri.Kuyeza magetsi kulinso vuto.
Silver kumira ndondomeko ndi pakati ❖ kuyanika organic ndi electroless faifi tambala / golide plating, ndondomeko ndi yosavuta komanso mofulumira;Ngakhale atakumana ndi kutentha, chinyezi ndi kuipitsa, siliva amatha kukhalabe ndi weldability wabwino, koma adzataya kuwala kwake.Silver plating ilibe mphamvu yabwino ya nickel plating / golide plating chifukwa palibe faifi pansi pa wosanjikiza wa siliva.
Ubwino: Njira yosavuta, yoyenera kuwotcherera opanda lead, SMT.Pamwamba kwambiri, otsika mtengo, oyenera mizere yabwino kwambiri.
Zoipa: Zofunika kwambiri zosungira, zosavuta kuipitsa.Mphamvu zowotcherera zimatha kukhala zovuta (vuto la micro-cavity).Ndiosavuta kukhala ndi electromigration phenomenon ndi Javani kuluma chodabwitsa cha mkuwa pansi pa kuwotcherera kukana filimu.Kuyeza magetsi kulinso vuto
Poyerekeza ndi mvula ya golide, pali wosanjikiza wowonjezera wa palladium pakati pa faifi tambala ndi golide, ndipo palladium imatha kuletsa dzimbiri zomwe zimachitika chifukwa cholowa m'malo ndikukonzekera mokwanira kugwa kwa golide.Golide amakutidwa kwambiri ndi palladium, zomwe zimalumikizana bwino.
Ubwino: Oyenera kuwotcherera opanda lead.Pamwamba kwambiri, oyenera SMT.Kudzera mabowo angakhalenso faifi tambala golide.Kusungirako nthawi yayitali, mikhalidwe yosungira si yovuta.Oyenera kuyesa magetsi.Zoyenera kusinthana ndi mawonekedwe.Oyenera kumangirira waya wa aluminiyamu, oyenera mbale wandiweyani, kukana mwamphamvu kuwononga chilengedwe.
Kuti muwonjezere kukana kwa mankhwalawa, onjezani kuchuluka kwa kuyika ndi kuchotsa ndi electroplating golide wolimba.
Kusintha kwa njira ya mankhwala a PCB sikuli kwakukulu kwambiri, kumawoneka ngati chinthu chakutali, koma ziyenera kudziwidwa kuti kusintha kwapang'onopang'ono kwa nthawi yayitali kumabweretsa kusintha kwakukulu.Pankhani yowonjezereka yoyitanitsa chitetezo cha chilengedwe, njira yochizira pamwamba pa PCB idzasintha kwambiri mtsogolo.