Restriction of Hazardous Substances Directive 2002/95/EC ( RoHS 1 ) is the abbreviation of the Directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment . It was adopted by the European Union in February 2003.

English R estrictio the o f H azardous S ubstances Directive (Restriction of the Use of Certain Hazardous Substances) consist of the first letters of the word.

The RoHS directive came into effect on July 1, 2006 and is required to come into effect and has become law in every member state. This directive (with exceptions) restricts the use of ten hazardous substances in the manufacture of various electronic and electrical equipment. It is closely linked to the Waste Electrical and Electronic Equipment Directive (WEEE) 2002/96/EC (now superseded<>), which sets collection, recycling and recovery targets for electrical products and is part of a legislative initiative to address the problem of large volumes of toxic electronic waste.

This phenomenon is mostly seen with all lead-free alloys. Gas escape to the outside causes bubble formation on the solder joint surfaces. There is no definitive reason for this phenomenon, although some suspected causes include:

Finish on the pads: This is more visible on ImAg surface finishes, especially those with high organic content.

Flux trapped in volatile materials.

Poor coating on PTH.

Lead-free has a lower density than Sn/Pb so any volatile gas is less buoyant in lead-free. (Lower power pushing the gas out)

In Europe, there is currently no indication of substances to be added to the banned substances list, other than those included in the RoHS directives. JEITA recommends that lead-free alloys contain silver. Because of the need to complete the desired wetting characteristics, silver is a critical additive.

1) Low Temperature Soldering :
High-power, integrated heaters, tips and the lowest on the market with thermocouple temperature soldering iron and repair station.

2) Read & Feed :
U extending copper wire is used for this. Thermocouple and heater element is a combination of the two is microprocessor controlled. 140wattlık work with 60 Hz per second with a transformer. Therefore, thermal performance is unbeatable.

3) Starting temperature :
10 to 90 seconds to reach 360°C in a conventional system. Only 2 seconds to reach this temperature Any JBC station.

4) Long-Life End : soldering iron is left is left to stand, the tip temperature is automatically reduced to 200 ° C. Thus, oxidation and corrosion is reduced. Compared with the conventional tip 3-5 times longer it means life. When the temperature is reached immediately taken from the soldering iron stand again.

Note: the tip geometry, temperature setting, solder, flux and vary depending on the wearer but generally between 25,000 and 100,000 solder joints can be created.

5) Change Quick Tip : There is no need for any tools to change the tip. Just place the holder, pull and insert the new tip. Quick tip changes reduce lost time.

6) Ergonomic Design : The JBC lightest available, they are the smallest and most ergonomic soldering iron.

7) Process Control : Take control of your process in your hand! Set temperature limits, read counters, lock the station with a PIN code or key against unwanted use.

8) Intelligent Thermal Control System :
Extend tip life by reducing temperature and energy use. It consumes only 4 watts in sleep mode.

9) Easy Calibration :
JBC technology is microprocessor controlled because there is no need to recalibrate any of the JBC stations. If desired, however, it can be easily done using the soldering tip TI2800 thermometer calibration.

10) High Efficiency : According to JBC soldering station technology with the best performance on the market 80% more efficient. In the following graphs, based on practical tests show this superiority.

The time to reach 350 °C
The graph below shows the performance of heating, competing with JBC soldering.

Result
JBC has fast thermal response irons on the market.

Process for 3 solder joints
The chart below shows the performance of the 3-port row to the same device. Thermal reaction at a temperature of 70° C than competing devices falling due to the weak, JBC also experiencing falling only 30°C. Soldering difference increases even more open.

Result :
Equipment JBC soldering at 350°C can effectively, can rival devices

Life would be much easier if, as an engineer, we made purchasing decisions based on a single factor. For example, the one that offers the highest electrical power. Unfortunately, real life is not like that. To understand what these powers mean, you have to take a closer look. If we take a hot air system with a 2.4kw top heater and compare it with PDR's 150w Focused IR system, you may think you have made up your mind right away. However, these figures may mislead you about the heat actually reaching the component.

The power of hot air systems must be higher than a PDR system so that it can compensate for the losses in the transition from heating element to component. If the PDR system increased its power to 2.4kw, the IR heater would probably burn a hole not only in the PCB but also in the table!

There are three types of technologies currently used in repair systems. These are hot air, Dark IR and PDR's focused IR system. Some companies have created a hybrid system by combining hot air and Dark IR technology.

The idea of combining these two technologies is to bring together the best features of both technologies, or if you look at it from the other side, it is to combine the worst features of the two methods.

The two most important factors are ease of use and efficiency.

Since we developed the Focused IR system in 1986, we have worked very closely with our customers to develop and improve our products in response to new challenges in the electronics industry. We paid special attention to the needs of operators and produced easy-to-use systems. We have made various types of products to meet our customers' most specific needs. For example, we built a system for an operator who had only 25% vision in one eye. It was critical for him to be able to do his job, otherwise he would lose his job. It was our pleasure to help him. Although we can design custom products, our systems are generally designed to be flexible enough to handle many modern repair applications.

Factors affecting efficiency include the chemicals used, heating, and the knowledge level of the operator. Thanks to the mechanical and software interface of our systems, anyone can achieve the same high standards after a short training.

As a person who sells and supports PDR Focused IR systems around the world, I always encounter the same problem. This problem is that various fluxes form a cocktail, blocking the solder balls (we are talking for a BGA) and making mechanical connections with the pads. Consider the following: a flux is originally used to solder the component; a second can be used to desolder the component, and a third can be used to remove old solder if you are using desoldering wire. A fourth is used to place the new component. The solder melts, but the mixture of various fluxes makes electrical contact while leaving a surface that prevents the ball from flowing onto the pads. This creates a problem that puzzles many engineers. Often (and incorrectly) attention is drawn to the repair station. Because they cannot believe or think that this is a chemical problem.

The final element to achieve the perfect repair process is the temperature profile (heating). We use a combination of shortwave focused IR from the top and medium wave IR from the bottom, controlled by a bespoke Automatic Profile Management system. So we double the temperature profiles in the original production. You can always achieve the best results by recreating the temperature profile used in production.

Medium wave IR preheats the PCB, preventing flaking and PCB sagging, and also overcomes the cooling effect of the horizontal plane. The rule of thumb is this: the larger the PCB surface to be preheated, the better.

It works like focused IR light. It has two main advantages; Firstly, you get what you see, or more importantly, you can see exactly what you get. Direct heating of neighboring components outside the light beam is not possible. Secondly, since it works just like a light, it can be brought to the desired power by controlling it from zero to maximum and from maximum to zero suddenly or step by step. This way, there is no delay for the heater to heat up or cool down. This means you can follow a temperature profile more closely than with any other repair technology.

Solder paste is a mixture of solder spheres held within a specialised form of solder flux. As the name indicates it has the texture of a paste, and hence the name.

The fact that it is a paste means that it can be easily applied to the board during PCB assembly.

The solder particles are a mixture of solder. Traditionally this used to be tin and lead, but with RoHS  legislation has been introduced around the world, to only use lead-free solders. These may be made from a variety of mixtures. One is 99.7% tin and 0.3% copper, whereas there are other mixtures that include other metals including tin.

• Solder paste must be stored under right conditions. For storage, please check here.

• Stir the solder paste slowly before using.

• Adjust solder paste diameter to minimum 20mm’s.

• Add solder paste regularly little by little.

• Set the temperature and humidity.

• Nerver dry solder paste on the stencil.

Between 0-8 °C; 3-6 months. In closed doors that doesnt hit day light in, you can store solder paste for a short time. Please check the expire date before you use.

Temperature:

Affects the viscosity.

Keep it in a proper cold.

Humidity:

Low humidity may dry the solder paste.

High humidity moustrises the solder paste.

Keep it in moderate humidity...

To determine the soldering iron tip life is very difficult. But with a good use, life will be much longer. If cleaning sponge is too wet, the soldering iron tip which is 350 °C, will suddenly drop to 100-150 ° C. By time, these temperature drops crack exterior cover and melts the copper inside. In this case, the tip life is even shorter than 1 week. (Thermal Shock)

Extra heated ends (such as at 400-450°C) quickly becomes unavailable. Heat must be set to minimum so that workflow is not disrupted. Such as 350 °C (High Temperature)

The material cleaning the soldering iron tip end (iron, tin) must be of a softer material. It must be made of brass so that the tip is not damaged by friction. (Soft Cleaning Wire)

The amount of flux in the solder and flux used should be minimal. Because flux contains acid and is one of the most important factors affecting the life. We do not recommend to use resin paste. Although it makes soldering easier, because of maximum acidity in these products it pierces the soldering tip. Then one must do the cleaning. The residue left may lead to a short circuit in the future.

In the images below, please see how does it melts the solder iron tip because of the excess amount of flux.

Under stencil cleaning rollers ensure that the screen of solder paste printing machines are kept clean and work efficiently, in other words, it is the cleaning roller for the bottom of the printing screen.

They are non-woven materials with a high durability rate, which do not leave dust and similar residues behind, are also suitable for vacuum cleaning and have a very high suction permeability, which are used for cleaning solder paste residues and other dirt-causing substances after solder paste printing. It can also be used wet or dry according to preference.

The machines suitable for the use of under-screen rolls are mainly ASM DEK and many other global brand machines and are available in different sizes according to demand. 400mm, 510mm and 600mm are the most preferred 3 types of under-screen rolls and you can view the length details of these rolls from the table below.

Model 1: 530mm x 510mm (53cm long)

Model 2: 530mm x 400mm (53cm long)

Model 3: 622mm x 600mm (60cm long)

Roll Type Main Width (A) Fabric Width (B) Roll Diameter (C) Inner Diameter (D) Roll Length (F)

400mm roll 530 mm 400 mm 56 mm 19 mm 10

510mm roll 530 mm 510 mm 56 mm 19 mm 10

600mm roll 622 mm 600 mm 56 mm 19 mm 10

You can examine the technical specifications of our high quality under stencil rolls that Assemcorp offers for sale below.

Main Components: 45% polyester, 55% cellulose

Weight: 68 g/m2

Thickness: 0.29 mm

2 to 15 minutes depending on the machine type and the amount of solder remaining on the stencil.

Fast drying cycles can be reduced so that the entire cleaning cycle is shortened. Alternatively, screens can be left to air dry. Thus, all the cleaning cycle is shortened. Outdoors it is maximum of 15 minutes of drying time. Even a slight air movement on the stencil may shorten outdoor drying cycle.

Dont forget!!!

The stencils are easy to break down - Use and store it carefully.

Keep it clean all the time.

Check for damage and stress.

Repair the fiducials when damaged ...

In manual cleaning:

• Use lint-free clothing.

• Clean both sides at the same time with clothing soaked with solvent. (use gloves!)
  

Under stencil cleaning:

• Programme to clean as much as possible!

• To clean the clogged apertures, use vacuum.

• After cleaning with a wet clothing, always use a dry one too...

With non-magnetic probes:

• Accurate, reliable and repeatable measurement is provided.

• Supports typical navigation applications on smartphones or special navigation devices.

• Used for test applications where normal probes disturb the magnetic field.

• Can measure three-axis movement without being affected by the test probe.

1 - Optical Analysis :
Optical inspection for the purpose of illuminated magnifiers and microscopes in the past has been used to date. Cards and better image smaller electronic devices has increased more vibrant and dynamic stereo vision and the high magnification imaging needs.

2 - Automatic Optical Inspection (AOI) :
Manual optical inspection systems, gives a detailed analysis and review opportunities for the detection of errors and quality problems. Series SMT production lines in less than a minute to string thousands of points of view, polarity, writing, offsets, presence-absence, should be able to examine the quality of solder and soldering errors. This automatic optical inspection systems are used to meet the need. SMT AOI inspection while the total investment can make more efficient production line can be abbreviated. Having a greater number of placement machines used in the production of SMD line card increases the cost of investment. In which the number of SMT circuit board member is busy occupying less space in the production area of the factory, unit investment costs for production lines in the string to reach the minimum number of machines with higher placement rate is significantly lower. Less energy is used to decrease the number of machines will occur less maintenance costs and operation and maintenance costs similar reasons, it can also be significantly reduced. A very busy board with a line of high-capacity SMD to be completed within 15-30 seconds. Very short cycle times in the string of automatic optical inspection of a card made must be able to be completed within the same period. AOI system must be able to keep up with the production line typesetting time and be able to complete all the required inspections quickly. Zero being the inability to capture the true error rate of the system in addition to the rapid test, not really fault error, it should report the error rate is low. In fact, failure to report as non-errors lead to unnecessary loss of time. AOI system, the separation of the faulty card without communicating to the next machine should also be collected from the interface of S and me. Modern AOI systems used in advanced lighting and camera systems are simple mistake and displayed outside thanks to the introduction of soldering failures can be more difficult to be identified. Easy programmability and OCR / OCV sought between features. Classifying errors and save the captured database server capable of Pareto analysis and statistical control, which communicates with its neighbors production and test equipment, information gathering and processing software available. For example TRI firm YMS (Yield Management System) receives information from the software testing and production devices are sent to the machine.

3 - Electrical and Functional Testing :
Electrical testing systems used to catch any errors that may occur in the circuit board at the end of the production line. Optical inspection with a soldering point seems proper, it does not provide information about the value of electrical circuit elements. Of electrical test and functional test methods it is possible to guarantee the proper functioning of the circuit board. To this end, in-circuit test (in-circuit test) production method using studded with bed bugs and function testing adapter (MDA or FCT) is made.

4 - X-ray Inspection :
The types of errors of each test and inspection methods that can detect the best on the circuit board varies. For example, the AO device with circuit elements on the articles can be read, offset material, can not obtain information about the polarity of the electrical disturbances denetletilebilirk internal structure of the circuit elements. X-ray examination, due to show the internal structure of the circuit board is a very powerful method. X-ray examination method is brought to the accumulated X-ray image on the computer screen. X-ray tomography images of a 3D micro method (MCTs), the error in images obtained by coupling it is possible to display a marked. Choosing the right fit for purpose x-ray system can be confusing criteria. The high power X-ray contrast can keep the same high geometric magnification thus ensures better quality of detail recognition. Because to increase the geometric magnification without sacrificing quality will bring to identify high-contrast detail. X-ray tube used in a small focal spot is how it may be that a sharp image. On the other hand focal spot [X-ray of the range out of the tube. So no matter how narrow this range can be achieved with a sharp image.] To be released from the smaller tube x-ray flux at that rate will be low. In this case, with minimization of the focal spot, and it will show the highest possible x-rays. Another important selection criterion for the X-ray image sensor system is also type. By making the usual x-ray systems in traditional x-ray phosphor coated on the surface appear analogue CCD [English Charged Coupled Device, analog image acquisition device] or CMOS [English Complementary Metal Oxide Semiconductor, an analog image pickup device] is converted to the camera image. CCD technology at Bell Laboratories in 1969 and developed by Willard Boyle and George Smith were commercialized in 1973. Other methods used in flat panel displays and digital X-ray system (DFPD [English Digital Flat Panel Detector, digital image sensing device.]) Is made in the image sensing. DFPD image sensor TFT technology with parallel time.This Philips, GE, Xerox has developed in Thomson and a number as a result of collective theoretical research and development started at the university during 1985-1990, and the first commercial product was introduced in 1997. DFPD image sensing technology in the analog signals that transmit the image in question is caused by electrical noise in the image tingling occurs. What improvements without interpolations with a real-time images and flicker-free image can be obtained. Traditional CCD image sensors of digital flat panel [i] Another advantage of the sensor are also being lighter. X-ray images to be examined in the system area and volume calculations can be performed from the electronic circuit board. Electronic circuit components inside the connecting wires, solder-plated holes of the inner fullness (barrel fill), the diameter of the cavity inside the BGA ball BGA ball deformities seen in and so on. calculations can be performed automatically. The automatic x-ray inspection systems for detailed reports and analysis instead of x-ray image of the AOI system lArIndAkine tested with similar image processing algorithms.

X-ray examination is a desirable feature not available in any other system is an advanced positioning capabilities of the axis. Lighter and can be manufactured in small digital flat panel detectors has lifted the axis positioning system that eliminates the necessity of a more cumbersome mechanical structure. To look at an angle to the card brings with it the rule incorrectly places to see from different angles. Card retention plate, image sensors and X-ray source is able to move independently and freely adjusted geometric magnification also be able to examine in detail the card. On many cards on the board with a circuit element X-ray image to be taken to examine the desired location is a desired feature quickly. X-ray image in the desired location can be time consuming to find. For this model Yxlon Cougar click and go (English Click & Move) feature for your convenience. Click and Go feature allows clicked on the location of the video image X-ray image appears on the screen in less than 1 second. Another feature of the model can be programmed y.coug also viewed the spot. The memory can be visited in order to examine the coordinates of the desired point, coordinates the program stored in memory can be saved to file. Later, when placed in the same card without the need to reconfigure the device immediately navigable between points of interest. Programming can also be taught as can be done by giving the coordinates.

We recommend starting at 255°C for a single side and 260°C for PTH. In general, wetting performance decreases as alloy temperature decreases.

1. Hand soldering
2. Soldering with melted solder
   1. Dip in soldering
   2. Wave soldering
   3. Drag soldering
3. Soldering with solder paste
   1. Reflow soldering
   2. Laser soldering

Without interfering with the chemical or physical structure, the bonding of same or different metals with each other both electrically and mechanically by using another metal or alloy as the filler or retention.

Only filler material moltens not the metals to be connected. Electronic soldering technology is used for connecting the components to each other or to the pad on the PCB both mechanically and electrically. As in all production, quality; is a chain of interconnected rings. Soldering is one of the most important ring in electronic production. No matter how well the design is, how good the components are selected, the quality of your production depends on the soldering bonding them.

Generally for leaded alloys tin and lead and for lead free alloys tin, silver and copper. According to the requirement, silver, copper , antimon or cadmium can be added as well.

As of 1 July 2006, according to RoHS directives transition is done both in Japan and EU. In US only in California transition started as of 1 January 2007. 1 June 2009 was the date for Turkey to start obeying RoHS directives.

• Thermal and mechanical resistance

• Wetting (soldering) capability

• Melting temperature

• Continuity

• Availability

• Patent Status

• Experience and references

• Price

• Flux allows solder to properly form between the pad and the component.

• It extends the life of the solder particles.

• It generates the correct viscosity and adhesion.

• It cleans the surface of pad and components.

• It cleans oxide in the solder particles.

• Protect surfaces during soldering.

Temel Kimyasal Tipleri

• RO; Rosin based

• RE; Resin based

• OR; Organic based

• IN; Inorganic based

Artık Aktivasyon Sınıfları

• L (Low); Activation

• M (Moderate); Activation

• H (High); Activation

For example: RO L0

• RO ; rosin

• L ; low activation

• 0 ; activator (halide) amount

Flux is the aiding material in soldering. Necessary for soldering, but after soldering no contribution and may even harm as a catalyst material.

FR-4 (or FR4) is a grade designation for glass-reinforced epoxy laminate material. FR-4 is a composite material composed of woven fiberglass cloth with an epoxy resin binder that is flame resistant (self-extinguishing).

"FR" stands for "flame retardant", and does not denote that the material complies with the standard UL94V-0 unless testing is performed to UL 94, Vertical Flame testing in Section 8 at a compliant lab. The designation FR-4 was created by NEMA in 1968.

FR-4 glass epoxy is a popular and versatile high-pressure thermoset plastic laminate grade with good strength to weight ratios. With near zero water absorption, FR-4 is most commonly used as an electrical insulator possessing considerable mechanical strength. The material is known to retain its high mechanical values and electrical insulating qualities in both dry and humid conditions. These attributes, along with good fabrication characteristics, lend utility to this grade for a wide variety of electrical and mechanical applications.

Grade designations for glass epoxy laminates are: G-10, G-11, FR-4, FR-5 and FR-6. Of these, FR-4 is the grade most widely in use today. G-10, the predecessor to FR-4, lacks FR-4's self-extinguishing flammability characteristics. Hence, FR-4 has since replaced G-10 in most applications.

FR-4 epoxy resin systems typically employ bromine, a halogen, to facilitate flame-resistant properties in FR-4 glass epoxy laminates. Some applications where thermal destruction of the material is a desirable trait will still use G-10 non flame resistant.

For FR2 style board materials, 255 °C is recommended, for some larger boards with heavy components - such as TV chassis - a central support cable is recommended to reduce the risk of sagging or bulging.

The highest temperature used in practice in production is 265 °C, no damage to components has been observed at this level. Temperatures above 270 °C are not recommended as they will shorten component life.

Ensure that Manufacturing Boards are free of ...

Fibers and dust: These can cause soldering errors and block screen apertures.

Old solder: Can cause solder balls.

Fingerprints: These can wear away or oxidize islands, vias (etc.). Handle boards by the edges and wear gloves ...

Under stencil cleaning rollers ensure that the screen of solder paste printing machines are kept clean and work efficiently, in other words, it is the cleaning roller for the bottom of the printing screen.

They are non-woven materials with a high durability rate, which do not leave dust and similar residues behind, are also suitable for vacuum cleaning and have a very high suction permeability, which are used for cleaning solder paste residues and other dirt-causing substances after solder paste printing. It can also be used wet or dry according to preference.

The machines suitable for the use of under-screen rolls are mainly ASM DEK and many other global brand machines and are available in different sizes according to demand. 400mm, 510mm and 600mm are the most preferred 3 types of under-screen rolls and you can view the length details of these rolls from the table below.

Model 1: 530mm x 510mm (53cm long)
Model 2: 530mm x 400mm (53cm long)
Model 3: 622mm x 600mm (60cm long)

Roll Type Main Width (A) Fabric Width (B) Roll Diameter (C) Inner Diameter (D) Roll Length (F)
400mm roll 530 mm 400 mm 56 mm 19 mm 10
510mm roll 530 mm 510 mm 56 mm 19 mm 10
600mm roll 622 mm 600 mm 56 mm 19 mm 10

You can examine the technical specifications of our high quality under stencil rolls that Assemcorp offers for sale below.

Main Components: 45% polyester, 55% cellulose
Weight: 68 g/m²
Thickness: 0.29 mm

1. Are apertures larger than pads?

2. Is there any space between stencil and the PCB?

3. Is stencil thicker than 0.150 mm?

4. Is stencil damaged?

5. Is the green dye thicker or thinner than the pads?

6. Are ther any solder masks, stickers and etc. near bridging?

7. Are tin coated pads smooth?

8. Is the viscosity of the solder paste too low? (metal ratio less than 89%)

9. Is printing area wet and hot?

10. Is squeegee wear down?

11. Is squeegee soft? (less than 90 shores)

12. Is squeegee pressure too high? (more than 2kg per 100 mm0)

13. Is printing misaligned?

1. Are there solder paste over the stencil surface?
2. Is squeegee torn down?
3. Is there a void between stencil and the PCB?
4. Is squeegee edge damaged?
5. Is squeege pressure too low? (for 100 mm squuegee width, less than 1 kg)
6. Are PCB supports weak?
7. Is stencil damaged?
8. Are there any solder paste, mark ink or similar material left around the area?

Is pressure area hot and wet?
Is squeegee soft ? (less than 90 shores)
Is squeegee pressure to high (more than 2kg per 100 mm)
Are the PCB supports weak?

1. Are there enough solder paste infront of the squeegee (app. 15 mm radius roll).
2. Does previous solder paste stick to squeegee?
3. Does the solder paste infront of squeegee drag instead of rolling?
4. Does the solder paste stay on the stencil surface?
5. Are apertures less than half of the pitch size?
6. Is the stencil thicker than 0.150 mm?
7. Are apertures clogging?
8. Is stencil deformed?
9. Is the green dye thicker or thinner than the pads?
10. Are ther any solder masks, stickers and etc. near misprinted?
11. Are tin coated pads smooth?
12. Is the viscosity of the solder paste too much?
13. Is solder paste old and dry?
14. Is the solder paste left on the stencil more than tens of minutes ?
15. Is it cold in printing area?
16. Is it uniform at squeegee edges?
17. Is squeegee blunt?
18. Are squeegee edges damaged?
19. Is squueegee speed too much for solder paste?
20. Is squueegee pressure too low? (for example less than 1kg/100mm squeegee length )
21. Are PCB supports weak?
22. Is squeegee too soft (less than 75 shores)
23. Is squeegee pressure to high? (for example more than 2kg/100mm through squeegee length).
24. Is seperation speed less than 0.5 mm/s or more than 10 mm/s?

1. Is PCB tensioned?

2. Is stencil deformed?

3. Are both fiducials for PCB and Stencil alingned?

4. Is it hard to find the Fiducials?

5. Do you need vision calibration?

6. Is the machine broken?

Printed circuit boards (PCBs) are often wave-soldered. However, some conditions make wave soldering difficult or expensive. Let’s take a look at the difference between wave and selective soldering.

Wave Soldering

Wave soldering is a bulk process where PCBs are passed over a wave of molten solder to attach through-hole (THT), surface mount technology (SMT), and mixed assemblies to circuit boards.

The major downside of wave soldering is the limited ability to define process parameters, which leads to poor solder joint quality and diminished product reliability. This limitation forces a one-size-fits-all approach to application and makes selectivity impossible. Solder washes over the board, applied universally, even where it is not required.

Additional, wave soldering disadvantages include:

High solder consumption
High flux consumption
High power consumption
High nitrogen consumption
An increase in post-wave solder rework
Masking of sensitive areas on PCB assemblies
Cleaning of wave solder aperture pallets or masks
Cleaning of soldered assemblies

With these significant disadvantages, wave soldering operating costs can be significantly higher when compared to selective soldering.

Selective Soldering

Selective soldering, also known as mini-wave soldering, offers cost-effective, repeatable results for THT and mixed technology soldering applications. Soldering points are individually programmed and monitored to control flux volumes and soldering time. And it is the only reproducible method for soldering THT components on a two-sided PCB assembly.

Selective soldering typically consists of three stages:

Fluxing or the application of liquid flux.
Preheating of the PCB assembly.
Soldering with a site-specific solder nozzle.

Selective soldering makes it possible to solder a wide range of PCB assemblies with advantages, including:

Secure and fast process optimization
Reliable solder joint creation without overheating components
Guaranteed process repeatability
The elimination of expensive wave solder pallets
The ability to solder around tall parts with tight spacing
The ability to solder dense concentrations of THT pins

All Nordson SELECT solutions come standard with nitrogen inerting, a titanium solder pot to resist the corrosive effects of aggressive lead-free solder alloys, and intuitive system software you can set up in minutes without prior experience.

Why Nordson?

You can be confident when choosing Nordson as your selective soldering partner. Our commitment to innovation, investment in R&D, and customer service excellence allow us to deliver consistent performance and reliability.

Download the Wave vs Selective Soldering Process Comparison Guide for additional process and cost information.

Explore Selective Soldering Solutions

There are many types of wave solder machines; however, the basic components and principles of these machines are the same. The basic equipment used during the process is a conveyor that moves the PCB through the different zones, a pan of solder used in the soldering process, a pump that produces the actual wave, the sprayer for the flux and the preheating pad.

• Conveyor
• Fluxer
• Pre-heating
• Pot
• Control System

The purpose of fluxer usage is to transfer neceessary amount of flux on the PCB surface homogeneously.

• Activates the flux.
• Dries the flux by vaporising the alcohol and water in it.
• Minimizes the warping of PCB during wave soldering.
• Protects the components and PCB towards thermal shock.
• Enhances the soldering speed.

• Cal rod preheaters
• Panel preheaters
• Infra-red glass panel preheaters
• IR Lamb preheaters
• Hot air panels

Minimum temperature in solder joint: Melting temperature + 50 °C
For 63/37 leaded solder 183 + 50 = 233 °C (Minimum)
Solder Pot temperature depends on intensity of the PCB.
The important thing is to set the temperature in a constant level.

• To clean smooth surface of solder pot
• To clean inside the solder pot
• To fix the solder level inside the pot

• Non-Wetting
• De-Wetting
• Voids in solder
• Short circuit
• Insufficient solder
• Fillet Lifting

Brass wool: Although less aggressive than the Inox Wool, it is easily subject to deterioration. It will cause metal particles and fibers to contaminate the working area. Customers have refused to use Brass Wool for this reason. Brass wool was first used in industry many years ago and it became standard use in industry and was used by many operators.

Inox Wool: It is more agressive than the Brass wool and so will require more care when being used. It is the most effective when used less aggressively and therefore minimizing the abrasions – Remember! Less Is Better. As well as being more effective, Inox is much more durable than Brass. It is more flexible, less fragile, and as a result, reduces the amount of particles and contamination of the work area. In tests we found it very resistant to breakage and it contained less than 10 times the amount of broken particles than in Brass wool.

Desoldering is a dirty task. When using our DR desoldering tool, it is recommended that you have a spare "tube", clean and set to go during the day. Simply unscrew the green end piece of the gun, remove it from the handle, take the tube off and replace it with the new one. This will allow you to continue working without stopping. Put aside 5-10 minutes at the end of a shift to use the extraction rod to take out the baffle and the filter in the glass or stainless steel tubes.

Take a small wire brush and gently brush the solder off the baffle into a trash receptacle or hazardous waste container (if using leaded solder). Replace the baffle to the mark on the tube and insert a new white filter. You should periodically check the secondary filter at the front (or back, depending on model) of the desoldering pump. Replace it when it looks dirty (discolored).

It is also a good idea to use the supplied drill bit tool to clean out the desoldering nozzles that you use to prevent buildup and clogging. The amount of useage your desoldering tool gets will determine the frequency of cleaning. Please see the manual for additional recommendations.

• Hand soldering
• Soldering with melted solder

1. 1. Dip in soldering
   2. Wave soldering
   3. Drag soldering

• Soldering with solder paste

1. 1. Reflow soldering
   2. Laser soldering

• To make a new soldering
• To repair a faulty soldering (Touch-Up)
• Rework

First of all, soldered to be area is heated with the soldering iron.
As solder wire contacts with the area, the solid flux in the wire melts around at 100°C and spreads on the area which makes it clean.
As solder reaches the melting temperature it melts and spreads on fully.
During the spread, an intermetallic layer is formed and soldering is finalizes.

To choose the correct soldering iron, tip and temperature,
To choose the right solder wire diameter,
To choose the appropriate solder alloy and flux,
Soldering process should be applied correctly.

Hand-soldering is a soldering method where soldering iron is used as the heater as well as flux containing solder wire.

ESD stands for english words "Electrostatic Sensitive Devices" or "Electro Static Discharge".

The static electricity is on a specific surface (-) of excess electrons load or (+) the lack of electrons load. Static electricity means the increase of electric charge on the surface of objects. This electric charge remains on an object until it either flows into the ground, or loses its charge quickly by a discharge. Uneven load distribution and accumulation in this way creates a voltage difference between the surface may interfere with their other surface. This gives rise to the danger of sparks and harmful discharge.

The aim of ESD control; in stages of transportation, distribution (logistics), production is to protect the sensitive electronic components against static discharge.

For ESD precautions to be effective, everyone should have has the necessary training and awareness in the production area and must move in accordance with certain rules. Periodic ESD checks should be done. The values must be measured on a regular basis and should be confirmed in the manufacturing field. There must be a person or team responsible for the ESD precautions and ensure the sustainability of these controls.

All environment related to ESD, IEC 61340-5-1 standard is available both in Europe and the world. IEC 61340-5-1 is the standard including test procedures and terms, approved ESD control, ESD products. IEC 61340-5-1 EPA (ESD protected area) should be used in areas with different ESD products also includes electrical properties.

Best Case: after the detection of faulty components, it is replaced. This means a minimum delay in production.

Acceptable Condition: the identification of the components is done in the last card test card. Components are replaced. And this means delay in production.

A difficult situation: the identification of the faulty card on the device, the components on the card is identified, the component is replaced and the long delays experienced in the production ...

Unacceptable situation: identification of the faulty one in the field. Staff is sent to field to identify. Defective cards and components are identified, the customer's production stops. Reputaion is totally damaged.

EPA (Electrostatic Protected Area); are working areas the buildup of static electricity t is prevented for sensitive electronic components. Marked boundaries of a E.P.A. is clearly defined and will be attracted by everyone's attention.

SMT is the abbreviation of the initials of the English words "Surface Mount Technology".

The production technology that uses surface mountable electronic components is called Surface Mount Technology. Before the use of surface mount elements, which are abbreviated as SMD to represent the initials of their English meaning, circuit assemblies could only be made with pinned circuit elements. Surface mount elements can be manufactured in much smaller sizes than pinned elements. Serial SMDs can be assembled with machines that include assembly robots. In this way, it is possible to design serial production and more miniature electronic circuits. Pinned circuit elements must be soldered by inserting them into holes in electronic cards and dipping them into a molten solder chamber, while SMDs are mounted directly on the card surface and then baked. The smallest chip component currently available in the industry is 008004 Size (0.25 x 0.125 mm). While small chips are mostly used only in devices that require high technology and require a small footprint (especially mobile phones, handheld computers, RF modules, etc.), it is possible to see larger SMDs in all types of electronic devices produced with surface mount technology.

What will the PCB’s Operating Environment be?

Coatings are applied in order to protect the PCB from corrosion in its operating environment. It is important then to consider the coatings ability to protect the board from its environment. The main questions which should be considered are:

• What temperature range will the board be exposed to?
• How rapidly will the operating temperature change (see thermal shock)
• What humidity will the board be operating in?
• Is condensation a consideration?
• Will there be salt present?
• Will it be immersed in water?
• What solvents will be present?
• What will be the level of UV present (daylight exposure)?

The coating must be suitable for use under the required operating conditions. Technical data sheets (TDS) are provided based on a range of internal and external tests according to international standards. Tests must also take place to ensure that the coating retains all the required properties throughout the duration of use. This is due to the differing conditions exhibited as a result of varying PCB materials and designs.

In addition to the performance characteristics of the cured coating, the application process plays an important role in the success (or otherwise) of the coating application and the following considerations should be made during the selection process:

Cure time available
Maximum cure temperature possible
Volume of boards to be produced
Available cycle time or TAKT time
Existing application equipment or new process?

What are the Electrical Requirements?

Conformal coatings form a protective, insulating layer. The most common electrical parameter tested is the Surface Insulation Resistance (SIR). This measurement is often taken before and after coating and exposure to harsh conditions, thus ensuring the coating continuously provides the level of insulation required. The coating should also exhibit high dielectric strength; the minimum required can be determined from the intertrack separation and the potential difference between adjacent tracks.

What will the PCB Board Layout be?

The design of the board should include consideration of the placement of components that should not be coated. Selective spray equipment or the application of a peelable coating mask can be used to help avoid such areas. Alternatively, gel materials can be used to form a ‘dam’ to contain the coating and avoid capillary effects transferring material to unwanted areas, such as connectors. Another aspect to consider is how close together the components are. If there is not sufficient gap between the components, it can lead to the coating bridging the gap rather than correctly conforming to the board, this can have a number of effects including the coating building up to become too thick and crack, or it can leave pockets under the coating where solvent can gather and cause corrosion.

Will it require Rework and Repair?
If the assembly requires repair then consideration must be given to the ease of removal of the coating. Electrolube offer products for the effective removal of conformal coatings, including those that are solvent resistant.

Removing Conformal Coating
Electrolube have a number of complementary products to assist with the removal of the coating, please see the section of the website here:- along with the TDS instructions.

What will the volume of production be?
The volume of production will have effect on a multiple of the other considerations mentioned in these articles. The most obvious being the application method and the cure times, for example automated applications will be preferable for mass production, whereas hand spray coating can be used on small runs.

What will be the final enclosure be like?
The mounting of the board in its final position can have an effect on the effectiveness of the coating for a number of reasons – for example, if the housing is open it will let more environmental elements in than a fully enclosed case. Whether the board is mounted horizontally or vertically is also very important, if possible it should be mounted vertically to avoid moisture from condensation sitting on the board.

The requirements of conformal coatings can differ from application to application. The most important properties that any conformal coating must have should be discussed first.

The ideal coating should offer a combination of:

• Good electrical properties
• Low moisture permeability
• Good physical characteristics
• Excellent adhesion to all board materials

To ensure the coating meets the desired characteristics, the coating needs to be exposed to a range of environments via appropriate test conditions to establish its performance range and limitations

Basic tests:
Electrical performance and accelerated humidity testing.

Advanced testing:
Severe conditions such as salt mist, temperature extremes or rapid environmental changes.
Electrolube put all of their conformal coatings through the test conditions outlined in these specifications and therefore, many other coatings from the range also meet the requirements of these standards. For full info on Product test results, please view the product TDS available from downloads.
Performance Criteria

Surface Insulation Resistance
The electrical resistance of an insulation material measured between two contacts.

When a board is coated it must have an electrical resistivity of 1010 ohms before environmental testing starts. After the tests, this value should not decrease below 108 ohms.

Flexibility
A coating must have a certain level of flexibility to ensure that all areas of the board will be coated sufficiently without any cracking or chipping upon cure. This will also ensure that the board can be moved and handled without damaging the coating and that an adequate level of flexibility is achieved in order to allow the PCB to expand and contract.

A strip of copper is coated and bent around either a 3mm mandrel to test.
The coating must not crack, delaminate from the substrate

Adhesion
Without adequate adhesion to the board the coating will not provide full protection. The cross-hatch test is a simple but effective way of measuring the adhesion of a conformal coating to standard circuit board materials.

A special tool is used to score lines in the coating in both directions, forming a
Cross-hatch pattern. An adhesive tape is then applied to the cross-cut area and carefully peeled away then the coating is inspected to see if any of the squares produced have been removed from the substrate.

Environmental Testing
Environmental testing is essential to ensure the required level of protection is achieved. End-use conditions should be replicated or accelerated, however care must be taken to ensure accelerated tests are suitable for comparison with end-use conditions:

Humidity Exposure and Salt Mist Testing
Thermal Cycling, Shock and Aging
These parameters are either tested individually or combined depending on the requirements

Environmental Cycling
Based on UL746 test methods, the following environmental cycling profile can also be utilised:

• 24 hours immersed in water, followed by
• 24 hours at 105°C, followed by
• 96 hours at 90%RH, 35°C, followed by
• 8 hours at -70°C – end of cycle
• 3 cycles

Humidity Tests
Humidity is probably one of the most obvious causes of corrosion for PCBs as moisture in the atmosphere can react with metal components and connections on the board. Humidity testing is carried out on a conformal coating to make sure that the resistance to this humidity is maintained.

Salt Mist Tests
Salt mist tests are important for any board which will be operating in an environment where there will be salt present. An obvious example of this is a marine environment such as electronics on shipping. Salt and water combined is one of the most highly corrosive combinations so it is imperative that adequate protection from this is provided.

Corrosive Gas Testing
Corrosive gas testing involves exposing PCBs to a mixed gas, environment combing hydrogen sulphide and sulphur dioxide BS EN 60068-2-60, method 1.

Surface insulation resistance (SIR) was used to determine the performance of each coating in this environment:

Electrical Testing
Evaluation of electrical properties is essential in all conformal coating applications. Some typical tests include:

• Dielectric Strength
• Dielectric Constant
• Dissipation Factor
• Surface Insulation Resistance
• Comparative Tracking Index (CTI)

Water Immersion
Immersion in water is an extremely harsh test for a conformal coating to pass. Most coatings will resist immersion for short periods of time however prolonged exposure can highlight issues.

Coated boards were immersed for 7 days and the SIR results compared.
For continuous or frequent immersion in water we advise Electrolube Encapsulation Resins
Solvent Resistance
During its lifetime a PCB may come into contact with any number of solvents, whether in the atmosphere of its working environment, or in direct contact.

Solvent resistance tests can be carried out in accordance with IEC 61086-2. The performance of the coating will largely depend on the solvents used during the test and the chemical makeup of the coating.

Thermal Cycling / Thermal Shock
Changes in temperature happen to a varying degree across most electronic applications due to fluctuations in the operating temperature or the surroundings.

As an example, if you think of a car starting up in winter, the standing vehicle in Europe can be as cold as -40°C, but once the engine is running the temperature of the engine quite rapidly rises to somewhere around 100°C (depending on the vehicle). The car could go through this thousands of times within its lifetime so it is important that products go through a thermal cycle test, or the more extreme thermal shock test (changing the temperature rapidly) to ensure the coating maintains the level of protection offered.

Thermal Cycle Test Example:
A thermal cycling profile was set up as per IEC 60068-2-14:

-55°C to +125°C, 25 minutes at each temperature
12°C/min rate of temperature change
20 cycles
Coated tin, copper, aluminium and FR4 panels were subjected to the cycling and then tested for adhesion (BS EN ISO 2409) and flexibility (3mm mandrel – IPC-TM 650 2.4.5.1)

Thermal Shock Test Example:
Thermal shock is similar to thermal cycling, but over a much faster time frame – Electrolube have recently bought a new machine to test for thermal shock, initial testing has taken place cycling a change of 190 °C in less than a minute.

UV Resistance
Electrolube have carried out weathering resistance tests on a number of available conformal coatings. Tests were in accordance with ISO 4892, Part 3, Cycle 1: ‘Plastics Methods of Exposure to Laboratory Light Sources’ and carried out in a QUV SE Accelerated Weathering Tester. After 1000 hours exposure, the results indicated that Electrolube acrylic coatings, APL and HPA for example, have superior resistance to UV light, maintaining their clarity throughout the exposure testing.

Exposure intensities will vary depending on geographical locations and therefore it is important to establish the correct accelerated exposure time for your region. As an example, this test is roughly equivalent to 4 years weathering resistance in a typical Northern European climate.

Conformal coating standards are a series of specifications and tests which a coating must pass in order to be considered for use in certain environments such as Military or Automotive applications.

Most conformal coatings are either qualified to MIL-I-46058C or meet the requirements of the closely related IPC-CC-830B specification. In addition they may be recognised by Underwriters Laboratories, either as a permanent coating, in which case the flammability of the coating is assessed to UL94V0, or as a conformal coating, where the electrical properties will be assessed as part of the UL746E standard.

These tests all require flat coupons to be coated with the conformal coating in question and are subjected to a variety of temperature and humidity conditions to assess the material’s properties. Whilst perfectly acceptable to assess the potential performance of the material, the actual protective capability of the coating in the end use environment is of greater concern to the user. The rest of this article will be devoted to understanding the issues that relate to end use performance in potentially corrosive environments.

MIL-I-46058C
Military Insulating Compound this is a common standard used throughout the industry for conformal coating materials. While it has been inactive for new designs since 1998, it is still a standard often required by military contractors. The main advantage of MIL-I-46058C is that it requires independent testing by a MIL approved laboratory (although at least one conformal coating manufacturer is an approved test laboratory so not completely independent!) and the military maintains a Qualified Product List (QPL) drawn from successful independent test reports.

Def Stan 59/47
The UK Ministry of Defence standard similar to the MIL-I-46058C this is a standard used by the British military for coatings used in high end electronics.

IEC 61086
International Electrotechnical Commission. Whilst similar in requirements to MIL-I-46058C, this standard is based on supplier self-certification. Of course, an independent test laboratory can be used, but the IEC does not maintain a QPL.

IPC-CC-830B
IPC-CC-830B is closely related to MIL-I-46058C and was introduced to provide an alternative to the MIL spec when it was declared inactive. CC-830 is an active specification and is continually being updated. Once again, there is no requirement to use an independent test laboratory, and there is no QPL maintained for this specification. Materials qualified to MIL-I-46058C are automatically deemed to meet the requirements of IPC-CC-830B.

UL94V0
UL94 relates to the flammability or self-extinguishing nature of the conformal coating on an FR4 substrate. V-0 is the highest classification that can be achieved, with other categories such as V-1 and V-2 denoting materials that burn for longer durations.

UL746E
UL746E is composed of a series of dielectric breakdown evaluations in addition to the UL94 flammability testing, and is intended to denote products that can be safely used on products that are required to meet UL safety standards. By documenting the use of UL recognised materials throughout the design, manufacturers can avoid the requirement to test their device to the applicable UL safety standards.

Environmental Standards
Here at Electrolube we believe that it is everyone’s responsibility, both individually, and as a business look after the world in which we all inhabit. Our R&D team are always looking at ways to minimise our environmental impact and we have several groundbreaking products as a result.

Policy:- Environmental Policy

VOCs – The Need for Change
Volatile solvents used in conformal coatings are classed as VOCs (Volatile Organic Compounds).
VOCs contribute towards the formulation of ground level ozone.
Such pollution can have many detrimental effects on the environment, damaging forests and vegetation.
In addition, some materials classed as VOCs can act as irritants and over exposure can lead to a variety of health problems.

VOC Definitions:
EPA
‘Volatile Organic Compounds (VOC) means any compound of carbon, excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates and ammonium carbonate, which participates in atmospheric photochemical reactions.’

EU Solvents Emissions Directive
‘Any organic compound with a boiling point less than or equal to 250˚C at a standard pressure of 101.3 kPa.’

Previously the directive referred to the definition as ‘Any organic compound, having at 20˚C a vapour pressure of 0.01KPa or more, or having corresponding volatility under the particular conditions of use’.

As stated on the European Commission website, either method is suitable:

The ‘boiling point approach’ was adopted for Directive 2004/42/CE because during negotiations Member States were generally more in favour of this definition of VOCs than the ‘vapour pressure approach’ definition in Directive 1999/13/EC. The main reason is that the boiling point of a substance is easier to identify (and presumably more data are available) than the vapour pressure at room temperature of the same substance. Nevertheless, the results of the two approaches for any one substance are, to the knowledge of the EU Commission, in most cases identical.’

Low VOC Alternatives
Products such as the Electrolube water-based coatings help to keep VOC levels to an absolute minimum without compromising on performance:

WBP ” Utilising hybrid technology, WBP offers the performance characteristics of a polyurethane coating, exhibiting excellent flexibility and solvent resistance. WBP is for dipping application methods.
WBPs – Is based on the same chemistry as WBP but specifically designed for spraying applications.
UVCL” utilises hybrid technology to provide extremely fast curing under suitable UV radiation. UVCL provides excellent protection under a wide range of environments and is characterised by better ‘no-clean’ compatibility and improved thermal shock resistance compared with other UV curable materials.
Electrolube are continually developing ‘greener’ technologies, helping to minimise solvent emissions and their impact on the environment.

REACH
Registration, Evaluation and Authorisation of Chemicals – the REACH system

RoHS regulations

Heat Cure Coating / Evaporation Cure Coating

Solvent based coatings cure by evaporation of solvents, this process can be accelerated in most cases by using heat, however this can affect the properties of the coating and cause coating defects if not performed correctly. In the case of Electrolube’s DCA for example, if you heat cure you get additional chemical resistance and greatly improved properties. Without heat cure, it offers good humidity protection. AFA, a non cross-linking solvent-based acrylic on the other hand, will reach the same protective capability regardless of the curing conditions, the use of heat just accelerates the process.

UV Cure Conformal Coating

UV curing uses intense ultraviolet light to set off a chemical reaction within the coating in order to cure almost immediately in areas exposed to the UV radiation. Due to the 3-D nature of most assemblies there will nearly always be areas that remain unexposed to the UV radiation (e.g. beneath components) and therefore a secondary cure mechanism is required. Moisture is the most common secondary initiation process since it does not require an additional process step, however formulations are available that use heat, although the cure times are relatively long (30 mins or more), and the temperatures are quite high (>120°C) which places additional thermal fatigue on the assembly.

Electrolube also offer UV cure coatings such as UVCLP and UVCLX which have a reliable chemical cure mechanism as the secondary process. This is considerably faster than the industry standard, with a full cure guaranteed in just 6-12 hours compared to up to two weeks or more with some products.

UV curing materials are popular in high throughput environments, since in most cases the parts can continue through the process within seconds of the curing process, thus speeding up manufacturing velocity and reducing Work In Progress (WIP).

Moisture Cure Coatings

Moisture cure coatings require moisture from the atmosphere to cure. The humidity in the atmosphere can affect the speed of cure; increasing the humidity will often speed up the process. Humidifiers can be added to conventional and IR ovens to provide greater humidity and accelerate this process. It is important that these products are handled with care. If containers are left open for long periods of time then moisture will be absorbed and the coating will begin to cure.

In the case of dip coating a dry argon blanket can be passed over the surface of the tank to ensure that the coating is kept dry whilst processing

The application method of a conformal coating is AS important, if not MORE important than the selection of the right material for your application. This is because even the best coating, when applied poorly will not provide the right levels of protection required.

To read more about this, please watch the video below.

Coatings can be categorised by their base chemistry, each option having its own beneficial properties for the different environments the PCB will be operating in. The most widely used materials are historically solvent-based, the benefits of which include:

• Ease of processing and application
• Simple viscosity adjustment
• Suitability for a range of application methods
• Tailored application and cure

Acrylic Coatings

Acrylics combine reasonable price with good environmental protection; they retain clarity and can resist darkening and hydrolysis during extended exterior exposure. They do however have a limited solvent resistance, making them suitable for re-work but not applications where chemical resistance is important.

Acrylic coatings offer good flexibility and all round protection
They offer excellent humidity and salt mist protection
They are easy to apply and remove and dry quickly at room temperature via simple solvent evaporation
They have a wide operating temperature range.
They have excellent adhesion to a wide variety of substrates

Polyurethane Coating

In contrast to acrylics, polyurethane coatings offer excellent chemical resistance and superior protection in harsh environments. They also maintain flexibility at very low temperatures. Like acrylics, they are also very versatile covering a broad operating temperature range.

Good flexibility, particularly at low temperatures
Excellent chemical resistance
Polyurethane coatings can be removed using specialist products (CCRG)
Very good abrasion resistance

Hybrid Coatings

Hybrid coatings are where a mixture of base chemistries are used. These can result in a number of different coating options, tailoring the requirements for specific applications.

Electrolube’s SCC3 range of conformal coatings are polyurethane base resins modified with silicone to enhance the high temperature properties of the resin. These coatings display a wide range of advantages over standard materials and as they are solvent-based, they also provide all the benefits of ease of application. The SCC3 range of coatings offers a wide range of performance benefits without the problems associated with standard silicone coatings; i.e. silicone migration and the effects of low molecular weight siloxanes.

Extremely wide operating temperature range
Easy to apply
Very high chemical resistance
Can be reworked with specialist coating removers (CCRG)
Good protection in a wide range of environments

Silicone Coatings

Generally speaking silicones are the most resistant coatings to high/low temperatures or temperature fluctuations due to their more flexible nature. These coatings offer a wide range of protection in a both challenging and rapidly changing environments. However they are less resistant to humidity and corrosive gases than other coating technologies.

Good all round protection
Flexible
Wide operating temperature ranges
Approved to IEC 61086 & IPC-CC-830
Ease of processing

Water-Based Coating

Water based coatings cure by evaporation of water from the system. They are low-VOC options, replacing the majority of solvent in the system with water. This improves operator safety and also dramatically reduces solvent emissions.

Reduces solvent use; improves operator and environmental safety
Electrolube products are NMP free; again offering a safer product
Electrolube products are hybrid products offering enhanced performance
Can be applied using standard equipment; dipping and spray versions available
Can offer a good level of chemical resistance

UV Cure Coating

UV cure conformal coatings are also another example of hybrid coatings. In this case, different chemistry types are often used to produce a dual-cure system, thus avoiding issues with areas shadowed from the UV light during curing. UV cure coatings offer the fastest curing times with coatings curing in seconds under UV light. This is extremely beneficial for high throughput applications and any shadowed areas will cure via the secondary cure system over time. Due to their highly cross-linked structure when cured, they can be difficult to remove and in some cases UV cure coatings are known to suffer from reduced flexibility during thermal changes and therefore must be carefully tested.

Extremely fast process times
Secondary moisture cure system used to help shadow areas cure
Good protection in a range of environments
Excellent chemical resistance

2K Coatings

2K two part coatings are hybrid technologies combining the best properties of encapsulation resins with those of a conformal coating. These materials offer some of the best protection available while maintaining the processability and cost effectiveness of a conformal coating (compared to a resin).

High Performance
High levels of protection in a range of environments
Applied more thickly than single part coatings
Excellent moisture protection

Whilst it is tempting to choose your coating based on cost factors, it is important to remember that to achieve the right level of protection from your coating material you will need to carefully select the right material for your application. Different types of coating will perform better in different operating environments, therfore selecting the best coating for your application is paramount to achieving the levels of protection you require.

We have provided the basis for you to make your selection here, however our unrivalled technical support team are always on hand to answer any queries you may have and to assist you in selecting the right material.

The use of conformal coatings is particularly important in automotive, military, aerospace, marine, lighting, industrial and green energy applications. However due to the rapid expansion of the electronics industry, conformal coatings are also finding their way into the domestic and mobile electronics industries, providing the necessary combination of high performance and reliability within a vast array of electronic devices.

A newly manufactured printed circuit board will generally perform well, but performance can quickly deteriorate due to external factors in its operating environment. Conformal coatings can be used in a wide range of environments to protect printed circuit boards from moisture, salt spray, chemicals and temperature extremes in order to prevent such things as corrosion, mould growth and electrical failures.

The protection provided by conformal coatings allows for higher voltage gradients and closer track spacing, in turn enabling designers to meet the demands of miniaturisation and reliability.

A conformal coating is a thin polymeric film applied to a printed circuit board (PCB) in order to protect the board and its components from the environment and corrosion.

The film is typically applied at 25-250µm and ‘conforms’ to the shape of the board and its components, covering and protecting solder joints, the leads of electronic components, exposed traces, and other metallised areas from corrosion, ultimately extending the working life of the PCB.

An original equipment manufacturer (OEM) traditionally is defined as a company whose goods are used as components in the products of another company, which then sells the finished item to users.

An EMS provider is now the term for a contract manufacturer in the electronics field that not only makes products for OEMs but also offers assistance with a wide array of value-added services, including: support with design, design for manufacture, supply chain management, configure-to-order, outbound logistics and repair elements.

EMS companies can be huge - in fact, they are multi-billion dollar businesses in their own right. So it’s not a surprise that they manufacture some of the world’s best-known products. For example, Microsoft's Xbox, Apple’s iPhone, HP printers, Cisco routers and a variety of products from companies like Sony and Nintendo are all believed to be built by Tier 1 EMS companies.

While these suppliers will often make "Top 10" lists, they specialise in manufacturing high volume, low complexity products and, as a result, demand multimillion-pound spend levels - which is why much of the world's consumer electronics end up shipping from their factories.

However, for OEMs that design and sell low to medium volume, often complex products, in sectors away from consumer electronics, Tier 1 suppliers may not be the most appropriate fit. Instead, OEMs are encouraged to take an alternative view of the EMS horizon, to find the most appropriate supplier for their business model and product range.

CEM stands for Contract Electronics Manufacturers.

ODM, or original design manufacturing, is also also referred to as “private labeling.” This is where an importer selects an already-existing product design from a factory catalog, makes a few small changes and sells it under their own brand name. Changes can include things like packaging or product bundles, colors and branding, and some limited adjustments to components or functionality.