Kusanthula kwatsatanetsatane kwa chigamba cha SMT ndi THT kudzera pa hole plug-in PCBA njira zitatu zotsutsana ndi utoto ndi matekinoloje ofunikira!

Pamene kukula kwa zigawo za PCBA kumakhala kocheperako komanso kocheperako, kachulukidwe kamakhala kokwera kwambiri; Kutalika kothandizira pakati pa zida ndi zida (mipata pakati pa PCB ndi chilolezo chapansi) kukucheperachepera, ndipo chikoka cha zinthu zachilengedwe pa PCBA chikuchulukiranso. Choncho, timaika patsogolo zofunika pa kudalirika kwa PCBA mankhwala pakompyuta.

1. Zinthu zachilengedwe ndi zotsatira zake

Zinthu wamba zachilengedwe monga chinyezi, fumbi, mchere kutsitsi, nkhungu, etc., zingayambitse mavuto osiyanasiyana kulephera PCBA

Chinyezi

Pafupifupi zigawo zonse zamagetsi za PCB zakunja zili pachiwopsezo cha dzimbiri, zomwe madzi ndizofunikira kwambiri pakuwonongeka. Mamolekyu amadzi ndi ang'onoang'ono kuti alowe mumpata wa ma molekyulu azinthu zina za polima ndikulowa mkati kapena kukafika pazitsulo zamkati kudzera pabowo la zokutira kuti ziwonongeke. Mpweya ukafika pachinyezi china, ukhoza kuyambitsa kusamuka kwa PCB electrochemical, kutayikira kwapano komanso kupotoza kwa ma siginecha mumayendedwe apamwamba kwambiri.

Mpweya/chinyezi + zoipitsa za ma ionic (mchere, ma flux active agents) = conductive electrolytes + stress voltage = electrochemical migration

Pamene RH mumlengalenga ifika 80%, padzakhala filimu yamadzi yokhala ndi makulidwe a 5 ~ 20 mamolekyu, ndipo mitundu yonse ya mamolekyu imatha kuyenda momasuka. Pamene carbon ilipo, ma electrochemical reaction amatha kuchitika.

Pamene RH ifika 60%, pamwamba wosanjikiza wa zipangizo kupanga 2 ~ 4 madzi mamolekyu wandiweyani madzi filimu, pamene pali zoipitsa kupasuka, padzakhala zimachitikira mankhwala;

Pamene RH <20% mumlengalenga, pafupifupi zonse dzimbiri zochitika kusiya.

Choncho, chinyezi-umboni ndi gawo lofunika kwambiri la chitetezo cha mankhwala. 

Pazida zamagetsi, chinyezi chimabwera m'njira zitatu: mvula, condensation ndi nthunzi wamadzi. Madzi ndi electrolyte yomwe imasungunula ma ion ambiri owononga omwe amawononga zitsulo. Pamene kutentha kwa gawo lina la zida ndi pansi pa "mame" (kutentha), padzakhala condensation pamwamba: zigawo structural kapena PCBA.

Fumbi

Pali fumbi mumlengalenga, fumbi adsorbed ion zoipitsa kukhala mkati mwa zipangizo zamagetsi ndi chifukwa kulephera. Ili ndi vuto lofala ndi zolephera zamagetsi m'munda.

Fumbi lagawidwa mitundu iwiri: fumbi coarse ndi m'mimba mwake wa 2.5 ~ 15 microns wa particles osasamba, zambiri sizingayambitse vuto, arc ndi mavuto ena, koma zimakhudza cholumikizira kukhudzana; Fumbi labwino ndi tinthu tating'onoting'ono tokhala ndi mainchesi osakwana 2.5 microns. Fumbi labwino lili ndi zomatira pa PCBA (veneer), zomwe zitha kuchotsedwa ndi burashi yotsutsa-malo.

Zowopsa za fumbi:a. Chifukwa cha fumbi kukhazikika padziko PCBA, electrochemical dzimbiri kwaiye, ndi kulephera mlingo ukuwonjezeka; b. Fumbi + chinyezi kutentha + mchere chifunga anayambitsa kuwonongeka kwambiri PCBA, ndi kulephera pakompyuta zida anali kwambiri mu makampani mankhwala ndi migodi dera pafupi ndi gombe, chipululu (saline-alkali dziko) ndi kum'mwera kwa Huaihe Mtsinje pa mildew ndi nyengo yamvula.

Choncho, chitetezo cha fumbi ndi gawo lofunika kwambiri la mankhwala. 

Kupopera mchere 

Mapangidwe a salt spray:Kupopera mchere kumachitika ndi zinthu zachilengedwe monga mafunde a m'nyanja, mafunde, kuthamanga kwa mlengalenga (monsoon), kuwala kwa dzuwa ndi zina zotero. Idzagwedezeka kumtunda ndi mphepo, ndipo kuchuluka kwake kudzachepa ndi mtunda wochokera kumphepete mwa nyanja. Nthawi zambiri, kuchuluka kwa kupopera mchere kumakhala 1% ya gombe pomwe ili pamtunda wa 1Km kuchokera kugombe (koma kumawomba patali nthawi yamvula yamkuntho). 

Kuopsa kwa mchere wothira mchere:a. kuwononga ❖ kuyanika kwa zitsulo structural mbali; b. Kuthamanga kwa electrochemical dzimbiri liwiro kumabweretsa kuthyoka kwa mawaya achitsulo ndi kulephera kwa zigawo. 

Magwero ofanana a dzimbiri:a. Thukuta la m'manja lili ndi mchere, urea, lactic acid ndi mankhwala ena, omwe ali ndi vuto lofananalo pazida zamagetsi monga kutsitsi mchere. Choncho, magolovesi ayenera kuvala panthawi ya msonkhano kapena ntchito, ndipo chophimbacho sichiyenera kukhudzidwa ndi manja opanda kanthu; b. Pali ma halogens ndi ma acid mu flux, omwe amayenera kutsukidwa ndikuwongolera ndende yawo yotsalira.

Choncho, kupewa kupopera mchere ndi mbali yofunika ya chitetezo cha mankhwala. 

Nkhungu

Kukungunda, dzina lodziwika bwino la bowa wa filamentous, limatanthauza "bowa wa nkhungu," amakonda kupanga mycelium wobiriwira, koma samabala zipatso zazikulu ngati bowa. M'malo achinyezi komanso otentha, zinthu zambiri zimamera m'maso, ena mwamagulu owoneka ngati ulusi, omwe ndi nkhungu.

CHITH. 5: PCB mildew chodabwitsa

Kuopsa kwa nkhungu:a. nkhungu phagocytosis ndi kufalitsa kumapangitsa kutchinjiriza kwa zinthu organic kuchepa, kuwonongeka ndi kulephera; b. Ma metabolites a nkhungu ndi ma organic acid, omwe amakhudza kutsekemera ndi mphamvu zamagetsi ndikupanga arc yamagetsi.

Chifukwa chake, anti-mold ndi gawo lofunikira lazinthu zoteteza.

Poganizira zomwe zili pamwambazi, kudalirika kwa mankhwalawa kuyenera kutsimikiziridwa bwino, kuyenera kudzipatula ku chilengedwe chakunja momwe zingathere, kotero kuti mawonekedwe opaka mawonekedwe amayambitsidwa.

Kupaka PCB mutatha kuyanika, pansi pa chowombera nyali chofiirira, zokutira koyambirira kumatha kukhala kokongola kwambiri!

Zopaka zitatu zotsutsana ndi utotoamatanthauza ❖ kuyanika wosanjikiza woonda zoteteza pamwamba pa PCB. Ndi njira yomwe imagwiritsidwa ntchito kwambiri pakuyatira pambuyo pa kuwotcherera pakali pano, yomwe nthawi zina imatchedwa zokutira pamwamba ndi zokutira conformal (dzina la Chingerezi: coating, conformal coating). Idzalekanitsa zida zamagetsi zamagetsi kumadera ovuta, zitha kusintha kwambiri chitetezo ndi kudalirika kwa zinthu zamagetsi ndikuwonjezera moyo wautumiki wazinthu. Zopaka zitatu zotsutsana ndi utoto zimatha kuteteza madera / zigawo kuzinthu zachilengedwe monga chinyezi, zowononga, dzimbiri, kupsinjika, kugwedezeka, kugwedezeka kwa makina ndi kuzungulira kwa kutentha, ndikuwongolera mphamvu zamakina ndi mawonekedwe otchinjiriza a chinthucho.

Pambuyo ❖ kuyanika ndondomeko PCB, kupanga mandala zoteteza filimu pamwamba, angathe kuteteza madzi ndi chinyezi kulowerera, kupewa kutayikira ndi dera lalifupi.

2. Mfundo zazikuluzikulu za ndondomeko yokutira

Malinga ndi zofunikira za IPC-A-610E(Electronic Assembly Testing Standard), zimawonetsedwa makamaka m'magawo awa:

Chigawo

1. Malo omwe sangathe kukutidwa:

Madera omwe amafunikira kulumikizidwa kwamagetsi, monga mapepala agolide, zala zagolide, zitsulo kudzera m'mabowo, mabowo oyesera;

Mabatire ndi okonza mabatire;

Cholumikizira;

fuse ndi casing;

Chipangizo chochotsera kutentha;

Jumper waya;

Diso la chipangizo cha kuwala;

Potentiometer;

Sensor;

Palibe chosindikizira chosindikizidwa;

Malo ena omwe kupaka kungakhudze magwiridwe antchito kapena ntchito.

2. Madera omwe akuyenera kuphimbidwa: zolumikizira zonse zogulitsira, zikhomo, zida ndi ma conductor.

3. Malo omwe mungafune 

Makulidwe

Makulidwe amayezedwa pa malo athyathyathya, osalepheretsa, ochiritsidwa a gawo losindikizidwa la dera kapena pa mbale yophatikizidwa yomwe imadutsa ndondomekoyi ndi chigawocho. Mapulani ophatikizidwa angakhale azinthu zofanana ndi matabwa osindikizidwa kapena zinthu zina zopanda porous, monga zitsulo kapena galasi. Muyezo wa makulidwe a filimu yonyowa ungagwiritsidwenso ntchito ngati njira yosankhira yoyezera makulidwe, bola ngati pali mgwirizano wolembedwa pakati pa makulidwe a filimu yonyowa ndi youma.

Table 1: Makulidwe osiyanasiyana amtundu uliwonse wazinthu zokutira

Njira yoyesera makulidwe:

1.Dry filimu makulidwe chida kuyeza: micrometer (IPC-CC-830B); b Dry Film makulidwe tester (chitsulo m'munsi)

Chithunzi 9. Micrometer youma filimu zida

2. Muyezo wa makulidwe a filimu yonyowa: makulidwe a filimu yonyowa amatha kupezeka ndi chida choyezera makulidwe a filimu yonyowa, kenako kuwerengeredwa ndi gawo la guluu olimba.

Makulidwe a filimu yowuma

Mu FIG. 10, makulidwe a filimu yonyowa adapezedwa ndi choyezera chonyowa cha filimu, ndiyeno makulidwe a filimu owuma adawerengedwa.

Kusintha kwa m'mphepete

Tanthauzo: Muzochitika zachilendo, kupopera kwa valve yopopera kuchokera pamphepete mwa mzere sikudzakhala kolunjika, nthawi zonse padzakhala burr. Timatanthawuza m'lifupi mwa burr ngati m'mphepete mwake. Monga momwe tawonetsera pansipa, kukula kwa d ndi mtengo wa kuthetsa m'mphepete.

Zindikirani: Kusanja kwa m'mphepete ndikocheperako bwino, koma zofunikira zamakasitomala zosiyanasiyana sizofanana, chifukwa chake mawonekedwe ophimbidwa m'mphepete mwake malinga ndi zomwe makasitomala amafuna.

Chithunzi 11: Kufananiza kwa malire

Kufanana

Guluu ayenera kukhala ngati makulidwe yunifolomu ndi yosalala ndi mandala filimu yokutidwa mu mankhwala, kugogomezera ndi yunifolomu guluu yokutidwa mankhwala pamwamba pa dera, ndiye, ayenera kukhala makulidwe ofanana, palibe mavuto ndondomeko: ming'alu, stratification, mizere lalanje, kuipitsa, capillary chodabwitsa, thovu.

Chithunzi 12: Axial zodziwikiratu AC mndandanda basi ❖ kuyanika makina ❖ kuyanika zotsatira, kufanana kumagwirizana kwambiri

3. Kuzindikira kwa ❖ kuyanika ndondomeko

Njira yokutira

1 Konzekerani

Konzani zinthu ndi zomatira ndi zinthu zina zofunika;

Dziwani komwe kuli chitetezo chapafupi;

Dziwani zambiri za ndondomekoyi

2: Sambani

Ayenera kutsukidwa mu nthawi yaifupi pambuyo kuwotcherera, kupewa kuwotcherera dothi n'zovuta kuyeretsa;

Dziwani ngati choipitsa chachikulu ndi polar, kapena chopanda polar, kuti musankhe choyeretsa choyenera;

Ngati mowa kutsukidwa wothandizila ntchito, nkhani chitetezo ayenera kulabadira: payenera kukhala mpweya wabwino ndi kuzirala ndi kuyanika ndondomeko malamulo pambuyo kutsuka, kupewa zotsalira zosungunulira volatilization chifukwa cha kuphulika mu uvuni;

Kuyeretsa madzi, ndi madzi oyeretsera zamchere (emulsion) kutsuka kutulutsa, ndiyeno muzitsuka ndi madzi oyera kuti muyeretse madzi oyeretsera, kuti mukwaniritse miyezo yoyeretsa;

3. Chitetezo cha masking (ngati palibe zida zoyankhira zomwe zimagwiritsidwa ntchito), ndiko kuti, chigoba;

Ayenera kusankha sanali zomatira filimu si kusamutsa pepala tepi;

Anti-static paper tepi iyenera kugwiritsidwa ntchito poteteza IC;

Malingana ndi zofunikira za zojambula za zipangizo zina zotetezera chitetezo;

4. Chotsani chinyezi

Pambuyo poyeretsa, PCBA yotetezedwa (gawo) iyenera kutsukidwa ndi kusungunuka musanaphike;

Dziwani kutentha / nthawi yowumitsa chisanadze malinga ndi kutentha komwe kumaloledwa ndi PCBA (gawo);

PCBA (gawo) akhoza kuloledwa kudziwa kutentha/nthawi ya tebulo chisanadze kuyanika

5 Chovala

The ndondomeko ❖ kuyanika mawonekedwe zimadalira zofunika chitetezo PCBA, zida alipo ndondomeko ndi nkhokwe alipo luso, amene nthawi zambiri zimatheka m'njira zotsatirazi:

a. Sambani pamanja

Chithunzi 13: Njira yotsuka m'manja

Burashi ❖ kuyanika ndi njira kwambiri ambiri ntchito, oyenera kupanga ang'onoang'ono mtanda, PCBA dongosolo zovuta ndi wandiweyani, ayenera kutchinga zofunika chitetezo cha mankhwala nkhanza. Chifukwa kupaka burashi kumatha kuyendetsedwa momasuka, kotero kuti mbali zomwe siziloledwa kupaka utoto sizidzaipitsidwa;

Kupaka burashi kumawononga zinthu zochepa, zoyenera pamtengo wapamwamba wa utoto wamagulu awiri;

Njira yojambula ili ndi zofunikira kwambiri pa woyendetsa. Asanamangidwe, zojambulazo ndi zofunikira zokutira ziyenera kugayidwa mosamala, mayina a zigawo za PCBA ayenera kuzindikiridwa, ndipo ziwalo zomwe siziloledwa kuti zikhale ndi zizindikiro zokopa maso;

Ogwiritsa ntchito samaloledwa kukhudza pulagi yosindikizidwa ndi manja awo nthawi iliyonse kuti apewe kuipitsidwa;

b. Kuviika ndi dzanja

Chithunzi 14: Njira yokutira divi m'manja

Njira yopangira dip imapereka zotsatira zabwino kwambiri zokutira. yunifolomu, zokutira mosalekeza zitha kugwiritsidwa ntchito pa gawo lililonse la PCBA. Njira yokutira yoviika siyoyenera ma PCba okhala ndi ma capacitor osinthika, kukonza maginito ma cores, ma potentiometer, maginito owoneka ngati chikho ndi magawo ena osasindikiza bwino.

Zofunikira zazikulu za njira yopaka dip:

Sinthani mamasukidwe oyenera;

Kuwongolera liwiro lomwe PCBA imakwezedwa kuteteza thovu kupanga. Kawirikawiri osapitirira 1 mita pamphindi;

c. Kupopera mbewu mankhwalawa

Kupopera mbewu mankhwalawa ndi omwe amagwiritsidwa ntchito kwambiri, osavuta kuvomereza njira, amagawidwa m'magulu awiri awa:

① Kupopera mbewu pamanja

Chithunzi 15: Njira yopopera mankhwala pamanja

Oyenera workpiece ndi zovuta, zovuta kudalira zochita zokha zida misa kupanga zinthu, komanso oyenera mankhwala mzere zosiyanasiyana koma zinthu zochepa, akhoza sprayed ku malo apadera kwambiri.

Chidziwitso ku kupopera mbewu mankhwalawa pamanja: nkhungu ya penti imawononga zida zina, monga pulagi ya PCB, socket ya IC, zolumikizirana zomveka ndi magawo ena oyambira, mbali izi ziyenera kulabadira kudalirika kwachitetezo chachitetezo. Mfundo ina ndi yakuti woyendetsa sayenera kukhudza pulagi yosindikizidwa ndi dzanja lake nthawi iliyonse kuti ateteze kuipitsidwa kwa pulagi kukhudzana pamwamba.

② Kupopera mbewu mankhwalawa

Nthawi zambiri amatanthauza kupopera mbewu mankhwalawa ndi zida zosankhidwa bwino. Oyenera kupanga misa, kusasinthasintha bwino, kulondola kwambiri, kuwononga chilengedwe pang'ono. Ndi kukweza kwa mafakitale, kuwonjezeka kwa mtengo wa ntchito ndi zofunika kwambiri pachitetezo cha chilengedwe, zida zopopera mankhwala zimasintha pang'onopang'ono njira zina zokutira.

Ndi kuchuluka kwazomwe zimafunikira pamakampani 4.0, cholinga chamakampanicho chasintha kuchoka pakupereka zida zoyenera zokutira ndikuthana ndi vuto la njira yonse yokutira. Makina opangira odzipangira okha - kuphimba molondola komanso osataya zinthu, oyenera kuphimba zochulukirapo, koyenera kwambiri pazopaka zitatu zotsutsana ndi utoto.

Kuyerekeza kwamakina opaka okhandimwambo ❖ kuyanika ndondomeko

Traditional PCBA zokutira utoto umboni atatu:

1) ❖ kuyanika burashi: pali thovu, mafunde, burashi tsitsi kuchotsa;

2) Kulemba: pang'onopang'ono, kulondola sikungathe kulamulidwa;

3) Kunyowetsa chidutswa chonse: utoto wowononga kwambiri, kuthamanga pang'onopang'ono;

4) Utsi kupopera mfuti: kuti fixture chitetezo, kutengeka kwambiri

Kupaka makina opangira makina:

1) Kuchuluka kwa utoto wopopera, malo opaka utoto ndi malo amayikidwa molondola, ndipo palibe chifukwa chowonjezera anthu kuti apukute bolodi pambuyo popaka utoto.

2) Zida zina zamapulagi zokhala ndi matayala akulu kuchokera m'mphepete mwa mbale zitha kupentidwa mwachindunji popanda kuyikapo, kupulumutsa ogwira ntchito kuyika mbale.

3) Palibe kutentha kwa mpweya, kuonetsetsa kuti malo ogwirira ntchito ali oyera.

4) Gawo lonse lapansi silifunikira kugwiritsa ntchito zida zophimba filimu ya kaboni, ndikuchotsa kuthekera kwa kugunda.

5) Ma yunifolomu atatu odana ndi utoto wokutira, amathandizira kwambiri kupanga bwino komanso mtundu wazinthu, komanso kupewa zinyalala za utoto.

PCBA automatic three anti paint coating machine, idapangidwa mwapadera kuti ipope zida zitatu zanzeru zopopera utoto. Chifukwa chakuti zinthu zomwe ziyenera kupopera ndi kupopera madzi zimagwiritsidwa ntchito ndizosiyana, makina okutira pomanga makina opangira zida amasiyananso, makina atatu odana ndi utoto amatengera pulogalamu yaposachedwa yoyang'anira makompyuta, amatha kuzindikira kulumikizana kwa olamulira atatu, pa nthawi yomweyo okonzeka ndi kamera udindo ndi kutsatira dongosolo, akhoza molondola kulamulira dera kupopera mbewu mankhwalawa.

Makina atatu opaka utoto, omwe amadziwikanso kuti makina atatu odana ndi utoto, makina atatu opopera mafuta opopera utoto, atatu opopera mafuta opopera utoto, makina atatu opopera utoto, omwe ndi apadera owongolera madzi, pa PCB pamwamba. yokutidwa ndi wosanjikiza atatu odana utoto, monga impregnation, kupopera mbewu mankhwalawa kapena sapota ❖ kuyanika njira pa PCB pamwamba yokutidwa ndi wosanjikiza photoresist.

Momwe mungathetsere nyengo yatsopano ya kufunikira kwa kupaka utoto katatu, kwakhala vuto lachangu lomwe likuyenera kuthetsedwa m'makampani. Zida zokutira zodziwikiratu zomwe zimayimiridwa ndi makina osankhidwa osankhidwa bwino zimabweretsa njira yatsopano yogwirira ntchito,❖ kuyanika molondola komanso osataya zipangizo, abwino kwambiri kwa ambiri atatu odana utoto ❖ kuyanika.