Inhloso enkulu ye- PCB ukubhaka ukukhipha uketshezi nokukhipha inyumbazane, ukususa umswakama oqukethwe ngaphakathi noma kumuncwe kusuka ngaphandle kwe-PCB, ngoba ezinye izinto ze-PCB kulula ukwenza ama-molecule wamanzi.

Ngaphezu kwalokho, i-PCBS nayo inethuba lokungenisa umswakama emvelweni ngemuva kokuthi ikhiqizwe futhi iboniswe isikhathi esithile, futhi amanzi angenye yezimbangela eziphambili ze-popcorn noma i-delamination. Lapho i-PCB ibekwa endaweni enezinga lokushisa elingaphezu kuka-100 ℃, njengesithando somlilo sangemuva, isithando samagagasi, ukwakheka komoya oshisayo noma inqubo yokushisela izandla, amanzi azophenduka umusi futhi andise ngokushesha ivolumu yawo.

Ngokushesha lapho i-PCB ishiswa, umhwamuko wamanzi uyanda. Ukuphakama kwezinga lokushisa, kukhulisa umthamo womphunga wamanzi; Lapho umusi wamanzi ungaphunyuki ku-PCB ngesikhathi, unethuba elihle lokufaka i-PCB.

Ngokuyinhloko, isiqondiso se-PCB se-PCB sisengozini enkulu, kwesinye isikhathi singaphula ukuhlangana phakathi kwezendlalelo ze-PCB, kwesinye isikhathi kungadala ukwahlukana phakathi kwezendlalelo ze-PCB, ngisho nokuvela kwe-PCB kungabonakala ukubhibhidla, ukwanda, ukuqhuma kwebhodi futhi ezinye izenzakalo;

Kwesinye isikhathi, noma ngabe i-PCB ingayiboni into engenhla ebusweni, empeleni ilimele ngaphakathi. Ngokuhamba kwesikhathi, kuzodala ukungazinzi kokusebenza kwemikhiqizo kagesi, noma i-CAF nezinye izinkinga, futhi ekugcineni kuholele ekuhlulekeni komkhiqizo.

Imbangela yangempela yokuhlaziywa nezindlela zokuvimbela ibhodi eqhume i-PCB

Eqinisweni, inqubo yokubhaka kwe-PCB inzima impela. Ukupakisha kwasekuqaleni kufanele kususwe ngaphambi kokuthi kufakwe kuhhavini, bese izinga lokushisa kufanele libe ngaphezu kuka-100 ℃, kepha izinga lokushisa akumele libe phezulu kakhulu, ukuze i-PCB izoqhuma ngenxa yokwanda ngokweqile komphunga wamanzi ngesikhathi sokubhaka.

Ngokuvamile, izinga lokushisa lokubhaka le-PCB livame ukusethwa ku-120 ± 5 ℃ embonini ukuqinisekisa ukuthi umswakama ungasuswa emzimbeni we-PCB ngaphambi kokuba umugqa we-SMT ushiselwe ngesithando somlilo sangemuva.

Isikhathi sokubhaka siyahlukahluka ngosayizi nosayizi we-PCB, futhi nge-PCB enosayizi omncane omncane noma omkhulu, ibhodi kufanele licindezelwe ngesisindo esisindayo ngemuva kokubhaka, ukuze kuncishiswe noma kugwenywe usizi lokugoba kwe-PCB okubangelwa ukukhululwa kwengcindezi ngesikhathi Ukupholisa i-PCB ngemuva kokubhaka.

Ngoba uma i-PCB ikhubazekile futhi igobile, inkinga ye-offset noma ubukhulu obungalingani izokwenzeka lapho unamathisela we-SOLDER ephrintiwe ku-SMT, okuzoholela kwinani elikhulu lokushisela isekhethi elifushane noma i-welding engenalutho neminye imicimbi emibi.

Isimo sokubhaka se-PCB

At present, the general conditions and time Settings for PCB baking are as follows:

1. I-PCB izovalwa kahle zingakapheli izinyanga ezi-2 kusukela ngosuku lokwenziwa. Uma i-PCB ingavaliwe futhi ibekwe endaweni elawulwa ngamazinga okushisa (≦ 30 ℃ / 60% RH, ngokwe-IPC-1601) izinsuku ezingaphezu kwezingu-5, izobhakwa ngo-120 ± 5 ℃ ngehora eli-1 ngaphambi kokuba ibekwe kulayini.

2. I-PCB izogcinwa izinyanga ezingaphezu kwezingu-2 ~ 6 ngemuva kosuku lokukhiqiza, futhi izobhakwa amahora amabili ngo-2 ± 120 ℃ ngaphambi kwe-inthanethi.

3. I-PCB kufanele igcinwe izinyanga ezingaphezu kwezingu-6 ~ 12, bese ithosiwe amahora amane ngo-4 ± 120 ℃ ngaphambi kokuthi iye ku-inthanethi.

I-4, isitoreji se-PCB izinyanga ezingaphezu kwezingu-12 zosuku lokukhiqiza, ngokuyisisekelo aluncomelwanga ukusebenzisa, ngoba amandla okunamathela ebhodini le-multilayer kepha azoguga ngokuhamba kwesikhathi, ukungazinzi komsebenzi womkhiqizo nezinye izinkinga zekhwalithi kungenzeka esikhathini esizayo, kwandise amathuba emakethe ukulungisa, futhi inqubo yokukhiqiza inokuqhuma kwebhodi futhi ukudla kwamathini kuyingozi enkulu. Uma kufanele usebenzise, ​​kunconywa ukubhaka ngo-120 ± 5 ℃ amahora ayisithupha, inani elikhulu lokunamathisela ngaphambi kokuphrinta ekukhiqizeni ukuqinisekisa ukuthi ayikho inkinga ye-solder ngaphambi kokuqhubeka nokukhiqizwa.

Enye ayinconywa isikhathi eside kakhulu i-PCB ngenxa yokwelashwa kwayo ebusweni ngesikhathi futhi kancane kancane nayo izokwehluleka, ku-ENIG, impilo eshalofini izinyanga eziyi-12, ngemuva kwalesi sikhathi, ngokuya ngosayizi wayo osindayo wegolide, uma ubukhulu buzacile, ungqimba we-nickel kungenzeka ngoba ukusabalala futhi kuvela kusendlalelo segolide nokwakheka kwe-oxide, kuthinta ukuthembeka, akunakuphaphama.

5. Onke ama-PCBS abhakiwe kufanele asetshenziswe kungakapheli izinsuku ezi-5, kanti ama-PCBS angalungisiwe kufanele abhakwe ngo-120 ± 5 ℃ ngelinye ihora eli-1 ngaphambi kokuya ku-inthanethi.

Ukunqwabelana kwe-PCB ngesikhathi sokubhaka

1. Usayizi omkhulu we-PCB kufanele ubekwe ngokuvundlile futhi ubeke isitaki lapho kubhakwa. Kunconywa ukuthi inombolo enkulu yesitaki akufanele yeqe izingcezu ezingama-30. Ukubhaka okumile akunconyelwe usayizi omkhulu we-PCB, kulula ukugoba.

2. Lapho kubhakwa i-PCB encane naphakathi nendawo, ingabekwa ngokuvundlile futhi ifakiwe, inani eliphakeme kakhulu lesitaki alikho izingcezu ezingaphezu kwezingama-40, noma lingasetshenziswa libheke phezulu nenombolo ayikhawulelwe. Ngemuva kwemizuzu eyi-10 yokubhaka, kuyadingeka ukuvula ihhavini bese ukhipha i-PCB bese uyibeka phezulu ukuyipholisa.

Amanothi wokubhaka kwe-PCB

1. Izinga lokushisa lokubhaka alingeqi iphuzu le-Tg le-PCB, futhi ngokuvamile alingeqi ku-125 ℃. Esigabeni sokuqala, iphuzu le-Tg le-PCB eliqukethe ukuhola laliphansi kakhulu, kepha manje i-Tg ye-PCB eningi ngaphandle kokuhola ingaphezu kuka-150 ℃.

2, ngemuva kokubhaka i-PCB kufanele isetshenziswe ngokushesha okukhulu, uma ingasetshenziswanga, kufanele iphinde ifakwe emaphaketheni ngokushesha okukhulu. Uma ivezwe kumasifundisane isikhathi eside kakhulu, kufanele iphinde ibhakwe.

3, kuhhavini khumbula ukufaka imishini yokumisa i-exhaust, ngaphandle kwalokho umusi wamanzi obhakwe uzogcinwa kuhhavini ukwandisa umswakama ohlobene nawo, ukukhishwa kwe-PCB okuphikisayo.

4. Ngokombono wekhwalithi, ukuvuselelwa kwe-PCB kabusha, ikhwalithi izoba ngcono ngemuva kokudlula esithandweni somlilo. I-PCB ephelelwe yisikhathi izoba nengozi ethile yekhwalithi noma ngabe isetshenziswa ngemuva kokubhaka.

Iziphakamiso zokubhaka kwe-PCB

1. Kunconywa ukubhaka i-PCB ngo-105 ± 5 ℃ inqobo nje uma amanzi abilayo eyi-100 ℃. Uma nje iphoyinti lokubilisa lidluliwe, amanzi azophendulwa abe umusi. Ngoba ama-PCBS aqukethe ama-molecule amaningi amanzi, awadingi amazinga okushisa aphezulu ukukhuphula ijubane le-gasification.

Izinga lokushisa liphezulu kakhulu noma isivinini se-gasification sishesha kakhulu, kepha kulula ukwenza ukwanda okusheshayo komhwamuko wamanzi, empeleni okungalungile ngekhwalithi, ikakhulukazi ebhodini elinemigqa eminingi ne-PCB enezimbobo ezingcwatshwe. I-105 ℃ ingaphezulu nje kwephoyinti lamanzi abilayo, futhi izinga lokushisa aliphezulu kakhulu, elinganciphisa amandla omzimba futhi linciphise ubungozi bokuba namachibi. Futhi ikhono lanamuhla lokulawula ukushisa kwe-ovini belingcono kakhulu kunakuqala.

2, NOKUTHI i-PCB idinga ukubhakwa, kufanele ibone ukuthi ukupakisha kumanzi yini, okungukuthi, ukubona ukufakwa kwe-VACUUM kwe-HIC (Humidity Indicator Card, Humidity Indicator Card) ikhombise ukumanzi, uma ukupakisha kukuhle, i-HIC Akukhombisi ukuthi kumanzi empeleni kungaba ku-inthanethi ngqo ngaphandle kokubhaka.

3. Kunconywa ukusebenzisa ukubhakeka “okuqondile” nokuhlukanisiwe kokubhaka kwe-PCB, ngoba kungale ndlela kuphela lapho ukushisa komoya okushisayo kungafinyelela umphumela omkhulu, futhi umusi wamanzi kulula ukubhakwa uphume kwi-PCB. Kodwa-ke, kuma-PCBS amakhulu osayizi, kungahle kudingeke ukuthi ubheke ukuthi ngabe uhlobo oluqondile luyobangela ukugoba kwepuleti yini.

4. Kunconywa ukuthi i-PCB ibekwe endaweni eyomile bese ipholile ngokushesha ngemuva kokubhaka. Kungcono ukucindezela i- “anti-plate bending fixture” ngaphezulu kwebhodi, ngoba into ejwayelekile kulula ukumunca umswakama kusuka kusimo esishisayo kuye kwinqubo yokupholisa, kepha ukupholisa okusheshayo kungadala ukuthi ibhodi ligobeke, okuthi idinga ukuthola ibhalansi.

Okubi kokubhaka kwe-PCB nezindaba ezidinga ukucatshangelwa

1. Ukubhaka kuzosheshisa i-oxidation ye-PCB surface coating, futhi uma izinga lokushisa liphakama, lapho ukubhaka kukubi ngokwengeziwe. 2, akunconywa ukwenza ukushisa okuphezulu kokushisa ebhodini eliphathwe ebusweni be-OSP, ngoba ifilimu ye-OSP izolulaza noma yehluleke ngenxa yokushisa okuphezulu. Uma kufanele ubhake, kunconywa ukubhaka ngo-105 ± 5 ℃ kungabi ngaphezu kwamahora ama-2. Kunconywa ukuthi usebenzise kuze kuphele amahora angama-24 ngemuva kokubhaka.

3, ukubhaka kungathinta ukukhiqizwa kwe-IMC, ikakhulukazi i-HASL (i-tin spraying), i-ImSn (i-chemical tin, i-tin dipping) yokwelashwa kwebhodi, ngoba ungqimba lwayo lwe-IMC (ithusi le-tin compound) empeleni kusesigabeni se-PCB yenziwe, okusho ukuthi, ngaphambi kokuzalwa kwe-PCB solder, ukubhaka kuzokhulisa ukushuba kwalolu ungqimba kukhiqizwe i-IMC, Dala izinkinga zokuthembana.