nkhani

Monga momwe tchati pamwambapa chikuwonetsa, PCB kumaliza ntchito kwakhala kosiyana kwambiri pazaka 20 zapitazi pomwe ukadaulo ukukula komanso kupezeka kwa mayendedwe okonda zachilengedwe.
1) HASL Itsogolere Kwaulere.Zamagetsi zachepa kwambiri kulemera ndi kukula popanda kusiya ntchito kapena kudalirika m'zaka zaposachedwa, zomwe zachepetsa kugwiritsa ntchito HASL kumlingo waukulu womwe umakhala wosagwirizana komanso suyenera kumveka bwino, BGA, kuyika kwazigawo zing'onozing'ono ndikukutidwa ndi mabowo.Kutsirizira kwa mpweya wotentha kumakhala ndi ntchito yabwino (kudalirika, kugulitsa, malo ogona ambiri otenthetsera kutentha ndi moyo wautali wautali) pa msonkhano wa PCB wokhala ndi mapepala akuluakulu ndi mipata.Ndi imodzi mwazotsika mtengo komanso zopezeka kumaliza.Ngakhale ukadaulo wa HASL wasinthidwa kukhala m'badwo watsopano wa HASL wopanda lead-free ku zoletsa za RoHS ndi malangizo a WEEE, kutha kwa mpweya wotentha kumatsika mpaka 20-40% mumakampani opanga zinthu za PCB kuchokera pakulamulira (3/4) m'derali m'ma 1980s.
2) OSP.OSP inali yotchuka chifukwa chotsika mtengo komanso njira yosavuta komanso kukhala ndi mapepala ogwirizana.Ikulandiridwabe chifukwa cha izi.Njira yokutira organic itha kugwiritsidwa ntchito kwambiri pa PCB wamba kapena ma PCB apamwamba monga phula labwino, SMT, matabwa.Kusintha kwaposachedwa kwa ma plate multilayer of organic coatings kuonetsetsa kuti OSP imayima mozungulira kangapo.Ngati PCB ilibe zofunikira zolumikizirana pamtunda kapena zoletsa za alumali, OSP ikhala njira yabwino kwambiri yomaliza.Komabe zolakwika zake, kukhudzika pakuthana ndi kuwonongeka, nthawi yayitali ya alumali, kusachita bwino komanso zovuta kuziwona zimachepetsa mayendedwe ake kuti akhale olimba.Akuti pafupifupi 25% -30% ya ma PCB pakali pano amagwiritsa ntchito njira yokutira organic.
3) ENI.ENIG ndiye kumaliza kodziwika kwambiri pakati pa ma PCB apamwamba ndi ma PCB omwe amagwiritsidwa ntchito m'malo ovuta, chifukwa chakuchita bwino kwambiri pamapulani, kukhazikika komanso kulimba, kukana kuwononga.Opanga PCB ambiri amakhala ndi nickel / mizere yomiza yagolide m'mafakitale awo a board kapena ma workshop.Popanda kuganizira za mtengo ndi kayendetsedwe ka kayendetsedwe kake, ENIG idzakhala njira ina yabwino ya HASL ndipo imatha kugwiritsidwa ntchito kwambiri.Mafuta a faifi tambala / kumiza golidi anali kukula mwachangu m'zaka za m'ma 1990 chifukwa chothana ndi vuto la kusanja kwa mpweya wotentha komanso kuchotsedwa kwa chitsulo chopangidwa ndi organic.ENEPIG monga mtundu wosinthidwa wa ENIG, idathetsa vuto lakuda lakuda la nickel / kumizidwa golide koma akadali okwera mtengo.Kugwiritsa ntchito kwa ENIG kukucheperachepera kuyambira pomwe kukwera kwamitengo yocheperako monga Immersion Ag, Immersion Tin ndi OSP.Akuti pafupifupi 15-25% ya ma PCB omwe akutengera izi.Ngati palibe mgwirizano wa bajeti, ENIG kapena ENEPIG ndi njira yabwino pazinthu zambiri makamaka kwa ma PCB omwe ali ndi zofunikira kwambiri za inshuwalansi yapamwamba, matekinoloje a phukusi, mitundu yambiri ya soldering, kupyolera-mabowo, mawaya ogwirizana, ndi teknoloji yoyenera yosindikizira, ndi zina..
4) Kumiza Siliva.Monga m'malo otsika mtengo a ENIG, siliva womiza wokhala ndi malo okhala ndi lathyathyathya kwambiri, ma conductivity apamwamba, moyo wamashelufu wocheperako.Ngati PCB yanu ikufuna kukweza bwino / BGA SMT, kuyika kwazigawo zing'onozing'ono, ndipo ikufunika kusunga kulumikizana bwino pomwe muli ndi bajeti yotsika, siliva womiza ndi chisankho chabwino kwa inu.IAg imagwiritsidwa ntchito kwambiri pazinthu zoyankhulirana, magalimoto, ndi zotumphukira zamakompyuta, etc.Kukula kwa siliva womiza kumakhala pang'onopang'ono (koma kumakwerabe) chifukwa cha kutsika kwanzeru kuwononga komanso kukhala ndi ma solder joint voids.Pali pafupifupi 10% -15% ya ma PCB omwe amagwiritsa ntchito kumaliza uku.
5) Kumiza Tin.Kumiza Tin wakhala akulowetsedwa mu ndondomeko yomaliza pamwamba kwa zaka 20.Production automation ndiye dalaivala wamkulu wa ISn surface finish.Ndi njira ina yotsika mtengo pazofunikira zapansi panthaka, kuyika kwa zigawo zabwino za mamvekedwe ndi makina osindikizira.ISn ndiyoyenera makamaka pazolumikizana zakumbuyo popanda zinthu zatsopano zomwe zawonjezeredwa panthawiyi.Tin Whisker ndi zenera lalifupi la ntchito ndiye kuchepetsa kwakukulu kwa ntchito yake.Angapo mtundu kusonkhana ali osavomerezeka kupatsidwa intermetallic wosanjikiza kuwonjezeka pa soldering.Kuphatikiza apo, kugwiritsa ntchito njira yomiza malata ndikoletsedwa chifukwa cha kukhalapo kwa ma carcinogens.Akuti pafupifupi 5% -10% ya PCBs panopa ntchito kumiza malata ndondomeko.
6) Electrolytic Ni/Au.Electrolytic Ni/Au ndiye woyambitsa ukadaulo waukadaulo wa PCB.Zawoneka ndi zadzidzidzi za Ma board adera Osindikizidwa.Komabe, mtengo wokwera kwambiri umalepheretsa kugwiritsa ntchito kwake.Masiku ano, Golide Wofewa amagwiritsidwa ntchito makamaka pawaya wagolide pakuyika chip;Golide wolimba amagwiritsidwa ntchito makamaka polumikizira magetsi m'malo osagulitsa monga zala zagolide ndi zonyamula IC.Gawo la Electroplating Nickel-golide ndi pafupifupi 2-5%.