As we all know, the continuous progress of electronic equipment and circuit technology, the peak of engineering art in the design, development and manufacture of ibhodi yesifunda ephrintiwe (I-PCB) ibonwe ngabantu emhlabeni jikelele. Our planet is full of highly intelligent machines, automated robots and scientific marvels, and of course, there are plenty of PCBS in every corner of the planet, no matter what country or city it is. Kodwa-ke, la ma-PCBS ahlukile ngokusebenza, ubunzima, izindleko zokwenziwa, ikhwalithi nokwethembeka. Lo mbhalo ugxile kumaphuzu amabili okugcina, ikhwalithi nokwethembeka kwe-PCBS.

Yebo, amakhasimende angaba khona ahlala efuna ama-elekthronikhi asezingeni eliphakeme, kepha lokhu kuyabiza kakhulu futhi kungafaka izinqubo eziyinkimbinkimbi zokukhiqiza. Enqubweni eyinkimbinkimbi yokukhiqizwa kwe-PCB, ukuhlangana nokuhlolwa, kunenqubo ebaluleke kakhulu ebizwa nge- “conformal coating” ye-PCB. Lokhu kumboza okuhambisanayo kubaluleke kakhulu kuma-PCBS ngokuya ngekhwalithi nokwethembeka.

Kuyini ukumboza okuhambisanayo nokubaluleka kwako:

Conforming coating, an ultra-thin protective coating of polymer film, can be used in conjunction with assemblies mounted on assembly surfaces to protect assembly leads, solder joints, exposed wiring, and other metal points on the PCB surface from corrosion, dust, or chemicals due to various operating or environmental conditions.

Ukumboza okuhambisanayo kungaba mncane njengama-microns angama-25 futhi “kuvumelana” nokuma nokwakheka kwengxenye yebhodi lesifunda. Njengoba kushiwo ngenhla, isizathu sokusebenzisa ukumboza okufanayo ebusweni (phezulu nangaphansi) kwe-PCB ukuvikela i-PCB ezimeni ezingezinhle zemvelo, ngaleyo ndlela kwandise impilo yesevisi ye-PCB nemishini ye-elekthronikhi ehambisana nayo.

Njengamazinga okushisa aphakeme atholakala ezimbonini, efektri, nakuma-elekthronikhi anamandla amakhulu, lawa ma-PCBS anezingubo ezihambisanayo angamelana namazinga okushisa adlulele. Ngokunjalo, okokusebenza kwe-elekthronikhi okufakwa ezindaweni / ezindaweni eziseduze nolwandle noma olwandle kungathinteka umswakama ophezulu, njengokuhamba kwemishini yasolwandle ye-elekthronikhi ingahle ibe ngaphansi kokugqwala / ukuguguleka okungaholela ekuhlanganisweni kwensimbi. Similarly, in microbiology laboratories and the medical industry, sensitive electronic equipment can be exposed to toxic chemicals, acidic and alkaline solvents that can accidentally spill onto a PCB, but the PCB’s “conformation coating” will protect the PCB and components from fatal injury.

Ungakufaka kanjani ukufaka okuhambisanayo?

In fact, the method of applying “conformal paint” in the right way is so important that careful consideration must be given to how conformal paint is applied. It is as important to choose suitable conformal coating materials.

Izici eziyinhloko ezinquma ukusetshenziswa okufanele kwezingubo ezihambisanayo yilezi:

1- Ubukhulu bepende

2- The level of coverage achieved

3- The degree of adhesion of paint to wood panels and their components.

There are five methods for applying conformal coatings:

1- Penda ngesandla ngebhulashi

I-2- i-Aerosol enamathela

3- Atomizing spray gun coating

4- Automatic dip coating

5- Automatic selection of coating

Indlela yokupholisa / yokumisa okwejwayelekile

Conformal coatings themselves can be classified according to the drying and curing methods used after conformal coatings are completed. These methods are:

1- Heat/heat curing: Conformal coating is dried at high temperature. Drying rate is much faster than normal room temperature drying/curing.

2- Ukuphulukiswa kwe-condensation: Ukumbozwa okuhambisanayo kwe-PCB komiswe emazingeni okushisa amancane, umswakama emkhathini wehlisa inqubo yokwelapha noma yokumisa.

3- ULTRAVIOLET (UV) curing: Here PCB with conformal coating is exposed to UV radiation. The uv energy determines the curing speed of PCB conformal coating

Ukuphulukiswa kwe-4- oxidation: Ngale ndlela, ama-PCB conformers adalulwa endaweni evulekile yomoya enenqwaba yomoya-mpilo osemkhathini, ozosiza ekomiseni / ekwelapheni kwama-conformers asekelwe

5- Catalytic curing: This is the process of curing conformal coating in which two materials are fused together, one of which is conformal coating. Lapho ukumbozwa sekuhlanganisiwe nezinye izinto zokwakha, inqubo yokwelapha ayikwazi ukumiswa ize iqede.

Classification of conformal coatings:

There are five main conformal coatings used: acrylic resin, epoxy resin, silicone, polyurethane (PU) and polyparaxylene coating.

L Acrylic resin (AAR):

Acrylics are ideal for (low-cost and high-volume) common electronics because AAR is inexpensive and can be easily applied to PCB surfaces by brush, dip, and manual or automatic spraying, reducing turnaround time and producing cost-effective products.

Izinzuzo:

1 – izindleko eziphansi

2- Kulula ukusetshenziswa kwezicelo zamarobhothi noma ezenzakalelayo

3- Easy to rework

4- Ukuvikelwa komswakama okuhle kakhulu

5- Good surface elasticity, can withstand static voltage discharge, and does not react with the atmosphere, therefore helps cure through solvent evaporation

Okumbi:

1- Due to the use of atmospheric curing/drying methods for this material, proper ventilation systems need to be ensured

2- Ukugcinwa kwe-viscosity ephansi

3- Ukumelana kokugqoka okuphansi nokumelana namakhemikhali

L Epoxy conformal coating (ER) :

Ukumbozwa okulingana okususelwa kuma-epoxy resins kungaqedwa ngebhulashi lesandla, isifutho noma idiploma yokumboza. Ukuncoma kuyanconywa kumanani amakhulu nakwevolumu elincane noma nge-prototype PCBS.

Izinzuzo:

1- High moisture resistance and good dielectric resistance

2- Excellent chemical resistance, abrasion resistance, moisture resistance and high temperatures up to 150 O C

Okumbi:

1-epoxy conformal paint is very hard and rigid and can damage PCB and its components if attempted peeling or removal. Susa ingubo ngokusebenzisa i-solvent eyingozi

2- Ukusebenza okushisa okuphansi okubi

3- Ukuphulukisa okuphezulu okuphulukisayo

4- Kunzima ukwenza kabusha

L Abicah resin (OSR) ukumboza okuhambisanayo:

The softest of the above two types of conformal coatings is silicone resin (OSR) conformal coatings. They are widely used in LED lamp PCBS without reducing light intensity or color change. Ideal for PCB installation at high humidity and exposure to air. Suitable for PCB with high operating temperature and high power

Izinzuzo:

1- Ukumelana okuhle kwamakhemikhali, ukumelana nomswakama, ukufafaza usawoti kanye namazinga okushisa aphezulu afinyelela ku-200 OC

2- Good flexibility makes it resistant to vibration stress on PCB from external environment.

I-3- Ifanele izicelo zangaphandle ze-PCB ezinomswakama ophezulu

Okubi:

1- Ungagqoki ukumelana ngenxa yezakhiwo zenjoloba

I-2- Ingavuselelwa kabusha, kepha hhayi kalula, idinga izincibilikisi ezikhethekile, izikhathi zokufaka isikhathi eside futhi ivuse njengebhulashi noma ibhavu ye-ultrasonic

3- Low mechanical strength, weak adhesion to PCB substrate

L Polyurethane (PU) ukumboza okuhambisanayo:

Ifanele izicelo ze-PCB ezimotweni, ezimbonini, ezinsimbi zomculo nakwezokuxhumana ngocingo. E-aerospace, ikakhulukazi, umusi kaphethiloli uhlala ushayisana nomzimba omkhulu wezinto zikagesi futhi ngaleyo ndlela ungene ngaphakathi futhi uthinte ibhodi le-PCB

Izinzuzo:

1- High resistance to moisture, chemicals (acid and alkali) and wear

Okumbi:

I-1- Ngemuva kwesikhathi eside senqubo ephelele yokwelapha, ijwayela ukuphuzi emazingeni okushisa aphezulu ngenxa yokuqukethwe kwayo okuphezulu kwe-VOC

2- Njenge-silicon, akulula ukususa ngokuphelele

L polyparaxylene conformal coating:

This type of coating is suitable for avionics, microelectronics, sensors, high-frequency circuits, and densely populated PCB-based components. It is applied by means of vapor deposition.

Izinzuzo:

1- Excellent dielectric strength

2- High resistance to moisture, solvents, extreme temperatures and acid corrosion

3- Can be applied evenly with very thin paint.

Okumbi:

I-1- Ukuqaqa / ukusebenza kabusha kunzima kakhulu

2- Izindleko eziphezulu ukubuyela emuva okukhulu.