PCB ndi gawo lofunikira kwambiri pamagetsi amakono komanso chonyamulira cha kulumikizana kwamagetsi pazinthu zamagetsi. Ndi chitukuko mosalekeza luso lamagetsi, kachulukidwe wa PCB ndi apamwamba ndi apamwamba, kotero pali zofunika kwambiri ndondomeko kuwotcherera. Choncho, m’pofunika kusanthula ndi kuweruza zinthu zimene zimakhudza PCB kuwotcherera khalidwe ndi kupeza zomwe zimayambitsa kuwotcherera zilema, kuti apange kusintha chandamale ndi kusintha khalidwe lonse la bolodi PCB. Tiyeni tione zomwe zimayambitsa kuwotcherera zilema pa PCB bolodi.

Chifukwa chiyani ma welds a PCB ali ndi zolakwika

Zifukwa za zolakwika za welding board ndi:

1. The weldability wa dzenje bolodi dera zimakhudza kuwotcherera khalidwe

dzenje weldability wa bolodi dera si zabwino, izo zidzatulutsa pafupifupi kuwotcherera zilema, zimakhudza magawo a zigawo zikuluzikulu mu dera, kutsogolera Kusakhazikika kwa zigawo multilayer bolodi ndi mkati mzere conduction, chifukwa kulephera kwa ntchito dera lonse.

Yuan Kunzhi kupanga fakitale yadzipereka kupatsa makasitomala ntchito zogulira zinthu pa intaneti, kupereka masauzande azinthu zamagetsi, kufunsa kwamitengo ndi malonda, kuwonetsetsa kuti zigawo zonse zikuchokera kufakitale yoyambirira kapena othandizira nthawi zonse kuti zitsimikizire kuti zoyambira authentic, ndi tsamba lanyumba la akatswiri apakompyuta

Zinthu zazikulu zomwe zimakhudza kugulitsa kwa matabwa osindikizidwa ndi awa:

(1) kapangidwe ka solder ndi mtundu wa solder. Solder ndi gawo lofunikira pakuwotcherera kwa mankhwala, limapangidwa ndi zinthu zomwe zimakhala ndi flux, zomwe zimagwiritsidwa ntchito motsika kwambiri zitsulo za eutectic ndi Sn-Pb kapena Sn-Pb-Ag. Zomwe zili mu zonyansa ziyenera kuyendetsedwa kuti oxide opangidwa ndi zonyansa asasungunuke ndi kutuluka. Ntchito ya flux ndi kuthandiza solder kunyowetsa dera pamwamba pa mbale soldered potengera kutentha ndi kuchotsa dzimbiri. White rosin ndi mowa wa isopropyl nthawi zambiri amagwiritsidwa ntchito.

(2) Kutentha kwa kuwotcherera ndi ukhondo wachitsulo pamwamba zidzakhudzanso kuwotcherera. Kutentha ndi okwera kwambiri, liwiro solder kufalitsa ndi inapita patsogolo, pa nthawi imeneyi ali ndi ntchito kwambiri, adzapanga gulu dera ndi solder Sungunulani pamwamba makutidwe ndi okosijeni, kuwotcherera zilema, dera bolodi padziko kuipitsa komanso zimakhudza weldability kubala zilema, kuphatikiza mikanda ya malata, mipira ya malata, mawonekedwe otseguka, gloss sizabwino.

2. Zowotcherera zolakwika zomwe zimachitika chifukwa cha kupotoza

Ma board ozungulira ndi zigawo zake zimapindika panthawi yowotcherera, zomwe zimapangitsa kuti pakhale zolakwika monga kuwotcherera komanso kuzungulira kwafupipafupi chifukwa cha kupsinjika kwamalingaliro. Warping nthawi zambiri amayamba chifukwa cha kutentha kutentha pakati pa kumtunda ndi kumunsi kwa bolodi la dera. Kwa PCBS yaikulu, warping imapezekanso pamene bolodi likugwera pansi pa kulemera kwake. Wamba PBGA zipangizo ndi za 0.5mm kutali ndi bolodi kusindikizidwa dera. Ngati zigawo zomwe zili pa bolodi la dera ndi zazikulu, mgwirizano wa solder udzakhala pansi pa kupsinjika kwa nthawi yaitali pamene bolodi la dera likubwerera ku mawonekedwe ake achibadwa pambuyo pozizira. Ngati chigawocho chikwezedwa ndi 0.1mm, chidzakhala chokwanira kuyambitsa dera lotseguka.

3, kapangidwe ka bolodi la dera kumakhudza mtundu wa kuwotcherera

Pamakonzedwe, kukula kwa bolodi la dera ndi lalikulu kwambiri, ngakhale kuwotcherera ndikosavuta kuwongolera, koma mzere wosindikizira ndi wautali, kusokoneza kumawonjezeka, mphamvu yotsutsa phokoso imachepa, mtengo ukuwonjezeka; Zochepa kwambiri, kutentha kwa kutentha kumachepa, kuwotcherera sikophweka kuwongolera, zosavuta kuwoneka mizere yoyandikana zimasokonezana, monga kusokoneza maginito amagetsi a bolodi. Choncho, PCB bolodi kapangidwe ayenera wokometsedwa:

(1) Kufupikitsa kugwirizana pakati pa zigawo zapamwamba kwambiri ndi kuchepetsa kusokoneza kwa EMI.

(2) Zigawo zolemera kwambiri (monga kupitirira 20g) ziyenera kukhazikitsidwa ndi chithandizo ndiyeno kuwotcherera.

(3) Kutentha kwa kutentha kwa zinthu zotenthetsera kuyenera kuganiziridwa kuti kupewe zovuta zazikulu za δ T pamwamba ndi kukonzanso, komanso zinthu zomwe zimakhudzidwa ndi kutentha ziyenera kusungidwa kutali ndi zotentha.

(4) Makonzedwe a zigawo monga kufanana mmene ndingathere, kotero kuti osati zokongola ndi zosavuta kuwotcherera, oyenera kupanga misa. 4∶3 kapangidwe ka bolodi lamakona anayi ndiabwino kwambiri. Osasintha makulidwe a waya kuti mupewe kutha kwa mawaya. Pamene bolodi la dera likutenthedwa kwa nthawi yaitali, zojambula zamkuwa zimakhala zosavuta kukulitsa ndi kugwa. Chifukwa chake, zojambula zazikulu zamkuwa ziyenera kupewedwa.

Mwachidule, pofuna kuonetsetsa khalidwe lonse la bolodi PCB, m’pofunika kugwiritsa ntchito solder kwambiri, kusintha solderability wa bolodi PCB, ndi kupewa warping kupewa zolakwika mu ndondomeko kupanga.