Lesi sihloko sihlaziya ikakhulukazi izinqubo ezimbili ezisetshenziswa kakhulu ku- PCB inqubo yokwelapha ngaphezulu: ikhemikhali ye-nickel yegolide nezinyathelo zenqubo ye-OSP nezici.

1. Igolide le-nickel lamakhemikhali

1.1 Izinyathelo eziyisisekelo

Ukwehlisa amafutha → ukugeza amanzi → ukungathathi hlangothi → ukugeza amanzi → ukuhushulwa okuncane → ukugeza amanzi → ukucwiliswa ngaphambili → ukwenza kusebenze i-palladium → ukufutha nokunyakazisa ukugeza amanzi → i-nickel engenawo ugesi → ukugeza amanzi ashisayo → igolide elingenawo ugesi → ukugeza amanzi kabusha → ukuwasha amanzi ngemva kokwelashwa → ukomisa

1.2 I-Nickel engenawo ugesi

A. Ngokuvamile, i-nickel engenawo amandla e-electroless ihlukaniswe ngezinhlobo “zokufuduka” kanye “nezinhlobo zokuziphendulela”. Kunamafomula amaningi, kodwa kungakhathaliseki ukuthi iyiphi, izinga lokushisa eliphezulu lokunamathela lingcono.

B. I-Nickel Chloride (i-Nickel Chloride) ngokuvamile isetshenziswa njengosawoti we-nickel

C. Ama-ejenti okunciphisa asetshenziswa kakhulu yi-Hypophosphite/Formaldehyde/Hydrazine/Borohydride/Amine Borane

D. I-Citrate iyona evame kakhulu ukuchela.

E. I-pH yesisombululo sokugeza idinga ukulungiswa nokulawulwa. Ngokwesiko, i-ammonia (Amonia) isetshenziswa, kodwa kukhona namafomula asebenzisa i-triethanol ammonia (Triethanol Amine). Ngaphezu kwe-pH eguquguqukayo kanye nokuzinza kwe-ammonia emazingeni okushisa aphezulu, iphinde ihlanganise ne-sodium citrate ukwenza ingqikithi yensimbi ye-nickel. I-agent ye-Chelating, ukuze i-nickel ifakwe ezingxenyeni ezicwecwe kahle futhi ngempumelelo.

F. Ngaphezu kokunciphisa izinkinga zokungcola, ukusetshenziswa kwe-sodium hypophosphite nakho kunethonya elikhulu kwikhwalithi yokugqoka.

G. Lena enye yezindlela zamathangi e-nickel amakhemikhali.

Ukuhlaziywa kwesici sokwakheka:

A. Umthelela wenani le-PH: i-turbidity izokwenzeka lapho i-pH ingaphansi kuka-8, futhi ukubola kuyokwenzeka lapho i-pH ingaphezu kuka-10. Ayinawo umthelela osobala kokuqukethwe kwe-phosphorus, izinga lokubeka kanye nokuqukethwe kwe-phosphorus.

B. Umthelela wezinga lokushisa: izinga lokushisa linomthelela omkhulu ezingeni lemvula, ukusabela kuhamba kancane ngaphansi kuka-70°C, futhi izinga lishesha ngaphezu kuka-95°C futhi alikwazi ukulawulwa. I-90°C ihamba phambili.

C. Ekugxilweni kokubunjwa, okuqukethwe kwe-sodium citrate kuphezulu, ukuhlushwa kwe-agent chelating kuyanda, izinga lokubeka liyehla, futhi okuqukethwe kwe-phosphorus kuyanda ngokuhlushwa kwe-agent chelating. Okuqukethwe kwe-phosphorus ohlelweni lwe-triethanolamine kungase kube phezulu kuze kufike ku-15.5%.

D. Njengoba ukugxila kwe-ejenti yokunciphisa i-sodium dihydrogen hypophosphite ikhula, izinga lokubeka liyakhula, kodwa isisombululo sokugeza siyabola uma sidlula u-0.37M, ngakho ukugxila akufanele kube phezulu kakhulu, ukuphakama kakhulu kuyingozi. Abukho ubudlelwano obucacile phakathi kokuqukethwe kwe-phosphorus kanye ne-ejenti yokunciphisa, ngakho-ke kufanelekile ukulawula ukugxila cishe ku-0.1M.

E. Ukugxiliswa kwe-triethanolamine kuzothinta okuqukethwe kwe-phosphorus ye-coating kanye nezinga lokubeka. Ukuphakama kwe-concentration, i-phosphorus content iyancipha futhi i-deposition ihamba kancane, ngakho-ke kungcono ukugcina ukugxila ku-0.15M. Ngaphezu kokulungisa i-pH, ingasetshenziswa futhi njenge-chelator yensimbi.

F. Kusukela engxoxweni, kuyaziwa ukuthi ukuhlushwa kwe-sodium citrate kungalungiswa ngokuphumelelayo ukuze kuguqule ngokuphumelelayo okuqukethwe kwe-phosphorus kwe-coating.

H. Ama-ejenti anciphisayo ahlukaniswe izigaba ezimbili:

Indawo yethusi ngokuvamile ayisebenzi ukuze ikhiqize ugesi ongemuhle ukuze kuzuzwe umgomo “wokucwenga okuvulekile”. Indawo yethusi isebenzisa indlela yokuqala ye-electroless palladium. Ngakho-ke, kukhona i-phosphorus eutectosis ekuphenduleni, futhi okuqukethwe kwe-phosphorus okungu-4-12% kuvamile. Ngakho-ke, lapho inani le-nickel likhulu, ukugqoka kulahlekelwa ukunwebeka kwawo kanye ne-magnetism, futhi i-gloss brittle iyanda, okulungile ekuvimbeleni ukugqwala nokubi ekubopheni izintambo nokushisela.

1.3 igolide alinawo ugesi

A. Igolide elingenawo ugesi lihlukaniswe “ngegolide elisuswayo” kanye “negolide elingenawo ugesi”. Owokuqala yilokho okubizwa ngokuthi “igolide lokucwiliswa” (i-lmmersion Gold plating). Isendlalelo sokucwebeza sincane futhi indawo engezansi icwecwe ngokugcwele futhi iyama. Lesi sakamuva samukela i-ejenti yokunciphisa ukuhlinzeka ngama-electron ukuze ungqimba lokucwenga luqhubeke nokujiya i-nickel engena-electro.

B. Ifomula yesici sokusabela kokunciphisa ithi: ukuncishiswa kwesigamu sokusabela: Au e-Au0 i-oxidation half reaction formula: Reda Ox e- full reaction formula: Au Red aAu0 Ox.

C. Ngaphezu kokuhlinzeka ngezakhiwo zomthombo wegolide kanye nama-ejenti anciphisayo, ifomula yokucwenga igolide engenawo ugesi kufanele futhi isetshenziswe ngokuhambisana nama-chelating agents, iziqinisi, izibhafa kanye nama-ejenti okuvuvukala ukuze isebenze kahle.

D. Eminye imibiko yocwaningo ibonisa ukuthi ukusebenza kahle kanye nekhwalithi yamakhemikhali egolide kuyathuthukiswa. Ukukhethwa kwama-ejenti okunciphisa kuyisihluthulelo. Kusukela ekuqaleni kwe-formaldehyde kuya kuma-borohydride compounds yakamuva, i-potassium borohydride inomphumela ovame kakhulu. Isebenza kangcono uma isetshenziswa ngokuhlangana namanye ama-ejenti anciphisayo.

E. Izinga le-deposit of the coating liyakhuphuka ngokwanda kwe-potassium hydroxide kanye nokunciphisa ukugxilisa kwe-ejenti kanye nezinga lokushisa lokugeza, kodwa liyehla ngokunyuka kokugxila kwe-potassium cyanide.

F. Izinga lokushisa lokusebenza lezinqubo ezidayiswayo licishe libe ngu-90°C, okuwuvivinyo olukhulu lokuzinza kwezinto.

G. Uma ukukhula kwe-lateral kwenzeka ku-substrate yesekethe encane, kungase kubangele ingozi yesifunda esifushane.

H. Igolide elincanyana lithambekele ekubeni ne-porosity futhi kulula ukulenza i-Galvanic Cell Corrosion K. Inkinga ye-porosity yongqimba oluncane lwegolide ingaxazululwa ngokuthi i-post-processing passivation equkethe i-phosphorus.