Kif nafu lkoll, il-progress kontinwu tat-tagħmir elettroniku u t-teknoloġija taċ-ċirkwit, il-quċċata tal-arti tal-inġinerija fid-disinn, l-iżvilupp u l-manifattura ta ‘ b’ċirkwit stampat (PCB) kien xhud minn nies madwar id-dinja. 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. Madankollu, dawn il-PCBS huma differenti fil-funzjonalità, il-kumplessità, l-ispiża tal-manifattura, il-kwalità u l-affidabbiltà. Dan l-artikolu jiffoka fuq l-aħħar żewġ punti, il-kwalità u l-affidabilità tal-PCBS.

Iva, klijenti potenzjali dejjem iridu elettronika ta ‘kwalità għolja, iżda din tiswa ħafna u tista’ tinvolvi proċessi ta ‘manifattura kumplessi. Fil-proċess kumpless tal-manifattura, immuntar u ttestjar tal-PCB, hemm proċess importanti ħafna msejjaħ “kisi konformi” tal-PCB. This conformal coating is very important in PCBS in terms of quality and reliability.

X’inhu kisi konformi u l-importanza tiegħu:

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.

Il-kisi konformi jista ‘jkun irqiq daqs 25 mikron u “jikkonforma” mal-forma u t-tqassim tal-komponent taċ-ċirkwit. Kif imsemmi hawn fuq, ir-raġuni għall-applikazzjoni ta ‘kisi konformi mal-wiċċ (fuq u isfel) ta’ PCB hija li tipproteġi l-PCB minn kundizzjonijiet ambjentali esterni avversi, u b’hekk iżżid il-ħajja tas-servizz tal-PCB u tagħmir elettroniku assoċjat.

Bħal temperaturi għoljin misjuba fl-elettronika industrijali, tal-fabbrika, u ta ‘qawwa għolja, dawn il-PCBS b’kisjiet konformi jistgħu jifilħu temperaturi estremi. Bl-istess mod, tagħmir elettroniku installat f’żoni / żoni qrib il-baħar jew l-oċean jista ‘jkun affettwat minn umdità għolja, bħal tagħmir navali elettroniku tan-navigazzjoni jista’ jkun suġġett għal korrużjoni / erożjoni li tista ’twassal għal ossidazzjoni tal-metall. 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.

Kif tapplika kisja konformi?

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.

Il-fatturi ewlenin li jiddeterminaw l-applikazzjoni xierqa tal-kisi konformi huma:

1- Ħxuna taż-żebgħa

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- Żebgħa bl-idejn b’pinzell

2- Kisi tal-ajrusol

3- Atomizing spray gun coating

4- Automatic dip coating

5- Automatic selection of coating

Metodu ta ‘vulkanizzar / tnixxif tal-kisi konformi:

Conformal coatings themselves can be classified according to the drying and curing methods used after conformal coatings are completed. Dawn il-metodi huma:

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

2- Tqaddid tal-kondensazzjoni: Il-kisja konformi tal-PCB titnixxef f’temperatura ambjentali, l-umdità fl-atmosfera tnaqqas il-proċess tat-tqaddid jew tat-tnixxif.

3- ULTRAVIOLET (UV) curing: Here PCB with conformal coating is exposed to UV radiation. L-enerġija uv tiddetermina l-veloċità tat-tqaddid tal-kisi konformi tal-PCB

4- Tqaddid bl-ossidazzjoni: F’dan il-metodu, il-konformaturi tal-PCB huma esposti għal ambjent ta ‘arja miftuħa b’ammonti kbar ta’ ossiġenu atmosferiku, li jgħin fit-tnixxif / tqaddid ta ‘konformaturi bbażati fuq is-solvent.

5- Catalytic curing: This is the process of curing conformal coating in which two materials are fused together, one of which is conformal coating. Ladarba l-kisi jiġi mdewweb ma ‘materjali oħra ta’ katalisti, il-proċess ta ‘tqaddid ma jistax jitwaqqaf sakemm jitlesta.

Classification of conformal coatings:

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

L Raża akrilika (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.

Benefiċċji:

1 – spiża baxxa

2- Faċli għal applikazzjonijiet robotiċi manwali jew awtomatiċi

3- Easy to rework

4- Protezzjoni eċċellenti mill-umdità

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

żvantaġġi:

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

2- Manutenzjoni ta ‘viskożità baxxa

3- Reżistenza baxxa għall-ilbies u reżistenza kimika

L Epoxy conformal coating (ER) :

Kisi konformi bbażati fuq reżini epoxy jistgħu jitlestew b’pinzell bl-idejn, sprej jew kisi dip. Il-bexx huwa rrakkomandat għal volumi akbar u għal volum iżgħar jew prototip PCBS.

Benefiċċji:

1- High moisture resistance and good dielectric resistance

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

żvantaġġi:

1-epoxy conformal paint is very hard and rigid and can damage PCB and its components if attempted peeling or removal. Neħħi l-kisi billi tuża solvent perikoluż

2- Prestazzjoni fqira f’temperatura baxxa

3- Tnaqqis ta ‘tqaddid għoli

4- Huma diffiċli biex jerġgħu jsiru

Kisi konformi tar-reżina tas-silikon (OSR):

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

Benefiċċji:

1- Reżistenza kimika tajba, reżistenza għall-umdità, sprej tal-melħ u temperaturi għoljin sa 200 OC

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

3- Adattat għal applikazzjonijiet ta ‘barra tal-PCB b’umdità għolja

Il-ħażin:

1- Mhux reżistenti għall-ilbies minħabba l-proprjetajiet tal-gomma

2- Jista ‘jinħadem mill-ġdid, iżda mhux faċilment, li jeħtieġ solventi speċjali, ħinijiet twal ta’ tixrib u tħawwad bħal pinzell jew banju ultrasoniku

3- Saħħa mekkanika baxxa, adeżjoni dgħajfa mas-sottostrat tal-PCB

Kisi konformi tal-Polyurethane (PU):

Adattat għall-applikazzjonijiet tal-PCB fil-karozzi, industrijali, strumentazzjoni u telekomunikazzjonijiet. Fl-ajruspazju, b’mod partikolari, il-fwar tal-fjuwil jaħbat kontinwament mal-korp ewlieni tat-tagħmir elettroniku u b’hekk jippenetraw ġewwa u jaffettwaw il-bord tal-PCB.

Benefiċċji:

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

żvantaġġi:

1- Wara żmien twil ta ‘proċess ta’ vulkanizzar komplet, għandu t-tendenza li jsir isfar f’temperaturi għoljin minħabba l-kontenut għoli ta ‘VOC

2- Bħal silikon, mhux faċli li tneħħi kompletament

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.

Benefiċċji:

1- Excellent dielectric strength

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

3- Can be applied evenly with very thin paint.

żvantaġġi:

1- Iż-żarmar / xogħol mill-ġdid huwa diffiċli ħafna

2- L-ispiża għolja hija l-akbar żvantaġġ.