PCB zofunika pakuyanika nickel si electrolytic

Chophimba cha nickel cha electroless chiyenera kukwaniritsa ntchito zingapo:

Gold deposit pamwamba

Cholinga chachikulu cha dera ndikupanga mgwirizano pakati pa PCB ndi zigawo zomwe zili ndi mphamvu zambiri zakuthupi ndi makhalidwe abwino amagetsi. Ngati pali okusayidi kapena kuipitsidwa pa PCB pamwamba, kulumikizana kogulitsidwa sikungachitike ndi kufooka kwamasiku ano.

Golide mwachilengedwe amatsitsa faifi tambala ndipo sangawonjezeke pakusungidwa kwanthawi yayitali. Komabe, golidi samatsika pa nickel oxidized, choncho nickel iyenera kukhala yoyera pakati pa nickel bath ndi kusungunuka kwa golide. Mwanjira iyi, chofunikira choyamba cha nickel ndikukhala opanda oxidation nthawi yayitali kuti alole mvula ya golide. Chigawochi chapanga madzi osambira omiza mankhwala kuti alole 6-10% ya phosphorous mu mpweya wa nickel. Izi phosphorous zili mu electroless faifi tambala ❖ kuyanika amaonedwa ngati bwino bwino kusamba kulamulira, okusayidi, ndi magetsi ndi thupi katundu.

kuuma

Chophimba cha nickel chosagwiritsa ntchito electrolytic chimagwiritsidwa ntchito pazinthu zambiri zomwe zimafuna mphamvu zakuthupi, monga zonyamula magalimoto. Zosowa za PCB ndizochepa kwambiri kuposa kugwiritsa ntchito izi, koma pakulumikiza mawaya

(Kulumikizana ndi mawaya), malo olumikizirana ndi pad, cholumikizira cholumikizira (m’mphepete-cholumikizira) ndi kukhazikika kwadongosolo, kuuma kwina kumafunikirabe. Kulumikiza mawaya kumafuna kulimba kwa nickel. Ngati chiwongolerocho chikusokoneza gawolo, kutayika kwa mikangano kumatha kuchitika, zomwe zimathandiza “kusungunuka” ku gawo lapansi. Chithunzi cha SEM chikuwonetsa kuti palibe kulowa pamwamba pa nickel / golide kapena faifi tambala/palladium (Pd)/golide.

Makhalidwe amagetsi

Chifukwa cha kupanga kwake kosavuta, mkuwa ndiye chitsulo chosankha kupanga madera. The conductivity yamkuwa ndi wapamwamba kuposa pafupifupi zitsulo zonse. Golide amakhalanso ndi magetsi abwino ndipo ndi chisankho chabwino kwambiri chazitsulo zakunja, chifukwa ma elekitironi amakonda kuyenda pamtunda wa njira yoyendetsera (“pamwamba” phindu).

Mkuwa 1.7 µΩcm Golide 2.4 µΩcm Nickel 7.4 µΩcm Electroless nickel plating 55 ~ 90 µΩcm Ngakhale mawonekedwe amagetsi a matabwa ambiri opanga sakhudzidwa ndi faifi wosanjikiza, faifi tambala zingakhudze mawonekedwe amagetsi a ma siginecha apamwamba kwambiri. Kutayika kwa chizindikiro kwa ma microwave PCB kumatha kupitilira zomwe wopanga amapanga. Chodabwitsa ichi ndi chofanana ndi makulidwe a faifi tambala – dera liyenera kudutsa mu faifi tambala kuti lifike pamagulu ogulitsira. M’mapulogalamu ambiri, chizindikiro chamagetsi chimatha kubwezeretsedwanso mkati mwazomwe zimapangidwira pofotokoza kuti faifisiti ya nickel ndi yochepera 2.5 µm.

Lumikizanani kukana

kukana kukhudzana ndi kosiyana ndi solderability chifukwa faifi tambala / golide pamwamba amakhala unsoldered mu moyo wa mapeto mankhwala. Nickel / golidi ayenera kukhalabe ndi mphamvu yamagetsi kuti agwirizane ndi kunja pambuyo powonekera kwa nthawi yaitali. Bukhu la Antler la 1970 limafotokoza zofunikira zolumikizirana ndi faifi tambala/golide mochulukira. Malo osiyanasiyana ogwiritsira ntchito mapeto amaphunziridwa: 3 ″ 65 ° C, kutentha kwapamwamba kwa machitidwe amagetsi omwe amagwira ntchito kutentha, monga makompyuta; 125 ° C, kutentha komwe zolumikizira wamba ziyenera kugwirira ntchito, zomwe nthawi zambiri zimatchulidwira ntchito zankhondo; 200 ° C, kutentha kumeneku kukukhala kofunika kwambiri pazida zowulukira.

Pamalo otsika kutentha, palibe chotchinga cha nickel chomwe chimafunikira. Pamene kutentha kumawonjezeka, kuchuluka kwa nickel kumafunika kuti tipewe kusamutsidwa kwa nickel / golide kumawonjezeka.

Nickel chotchinga wosanjikiza Kukhudzana kokwanira pa 65°C Kukhudzana kokwanira pa 125°C Kukhudzana kokwanira pa 200°C 0.0 µm 100% 40% 0% 0.5 µm 100% 90% 5% 2.0 µm 100% 100% 10% 4.0% 100% 100% 60% µm % XNUMX%