The Internet of things (IoT) allows us to connect everyday things to the internet. It is defined as a network of devices, vehicles, appliances, and other things that are connected. IoT is possible with the use of sensors, actuators, electronics, and software embedded into the later. Data collected from these physical devices are sent back and forth for better operation through network connectivity. A multitude of applications in defense, security, medical and industrial applications are available. Wearable devices, underwater systems, agricultural technologies, smart home applications, automotive, aviation systems and other areas of applications make use of IoT devices.Read More
Parylene Coating Blog by Diamond-MT
Liquid conformal coatings provide inexpensive, easily-applied insulative protection for printed circuit boards (PCBs) and similar electronics. However, the films’ otherwise desirable insulative qualities can interfere with operation of the assemblies’ electrical components, items like capacitors, connectors, diodes, resistors, or transistors, if these are coated. Liquid coatings are designed to "wick" under components and in between connectors to provide a complete coat, through brushing, dip-immersion, or spraying. These methods work exceptionally well, rendering an overall, dielectric conformal film for the PCB.Read More
A variety of coating equipment is available for use in the conformal coating process. The most important for liquid coatings are described below.Read More
Operationally, conformal coatings are applied to the surface of PCBs and related electrical components, to insulate and protect them during use. Coatings improve PCBs’ performance under any circumstances, but are especially valuable for their functional tolerance to harsher working environments.Read More
In the highly competitive conformal coatings’ industry, these providers stand out:Read More
Withstanding such complications to the operational environment as corrosion, fungus, oxidation, rain, salt water/mist, snow, temperature fluctuations or vibration is essential to long-term performance of electronic devices. Without suitable protection, printed circuit boards (PCBs) and similar electronics will not survive harsh environments, and malfunction. Prominent examples include:Read More
Conformal coatings made of acrylic resin (AR) are very popular, because of their distinctive beneficial properties. They protect printed circuit boards (PCBs) and similar electronics from corrosion, dirt, dust, fungus, moisture, and thermal shocks. Exceptionally user-friendly, liquid AR can be simply applied by brush, dip, or manual/robotic spray, generally resulting in the fastest turnaround-time of all conformal coatings. Ease of application and rework generates low cost for both manufacturer and client. AR’s moisture protection is also very highly rated, adding to its utility for a wide range of coating uses.Read More
As the name suggests, spray coating is a method of application where the conformal coating is sprayed directly onto the printed circuit board (PCB). It is typically applied manually in a spray booth or by aerosol, although it can be automated/robotic, for selective coating assignments.Read More
Conformal coatings insulate printed circuit boards (PCBs) and similar electronics; their protection increases devices’ tolerance to harsh environments. The result is undisturbed function through a range of frequently harsh operating environments and performance conditions. Conformal coatings provide these services for aerospace/defense, automotive, consumer, and medical devices. They are adaptable for LED uses, as well as MEMS/nanotechnology, and other uses.Read More
The conformal coating process requires watchful administration to ensure successful implementation. Recognizing the unique properties of various coating-types is critical to selecting the kind most applicable to the project and its purposes, while meeting clients’ material and operational specifications. Regardless of the coating material and the substrate, these five fundamental procedures are essential to good conformal films.Read More
Managing the conformal coating process begins with a precise definition of coverage required. Pre-process negotiations between the client, the coating provider, and end-user, clarify coating requirements. They include agreement about whether:Read More
Liquid application resins acrylic, epoxy, silicone and urethane are applied to electronic circuitry in a liquid format by brush, dip or spray techniques, either manually or through robotic processes; they require curing before they can be used.Read More
The value of polymeric conformal coatings for protecting printed circuit boards (PCBs) from functional retardants like dust, corrosion, moisture, and temperature fluctuations has been well-documented. Conforming to the physical configurations of the exposed face of the PCB, conformal coating:Read More
Although its basic component is remarkably small – with 25,400,000 nanometers included in just one inch(!!) -- nanotechnology encompasses a growing, interdisciplinary field with an unlimited future. Nanowires and nanotubes are used in transistors for printed circuit boards (PCBs) and associated electronic assemblies. Bio-nanobatteries, capacitators, LCDs, and microprocessors represent just a few nano-applications, which include uses for aerospace, agricultural, automotive, consumer, industrial, medical, military and oceanic products.Read More
Conformal coatings protect printed circuit boards (PCBs) and similar electronic assemblies used for a wide range of aerospace, automotive, consumer, defense and medical applications. Coatings effectively cover PCBs, shielding them from contaminants, liquid incursions, temperature fluctuations and other conditions potentially hazardous to component performance. However, problems can develop if their preparation, application, and drying processes are inappropriately managed.Read More
The engineering of functional systems at the molecular scale, nanotechnology encompasses management of individual atoms, combined into effective working units, often complex as machines. Yielding advantages like enhanced chemical reactivity and strength than larger-scale structures, they offer greater control of the light spectrum and weigh significantly less. Incredibly small, one nanometer is a billionth of a meter (10-9 of a meter) -- one inch equals 25,400,000 nanometers; more illustratively, a sheet of newspaper is 100,000 nanometers thick.Read More
Masking tapes and boots both protect components for a selected range of masking functions. Choosing between the two is crucial to achieving optimal masking protection. Conductivity needs to be maintained in all cases. In addition, such operational factors as the:Read More
Conformal Coating Masking BootsRead More
Printed circuit boards (PCBs) and related electrical assemblies benefit from the protection of conformal coatings. However, because the films are insulative when dry, they can disrupt operation of the assemblies’ electrical components, items like capacitors, connector contacts, diodes, operational amplifiers, resistors, or transistors. Conformal coating masking protects specified regions of PCBs and related assemblies from being conformally coated during film application. These components must remain uncoated to function as designed. Consisting of masking appliances constructed with appropriate materials, masking systems prevent migration of conformal coatings into designated keep-out areas. Masking processes enacted prior to coating application assure the conformal materials DO NOT invade designated keep-out areas.Read More
It is possible to remove unwanted conformal coatings from PCBs in-shop. The process can often be accomplished by either the assembly’s original equipment manufacturer (OEM) or an end-user, but the capacity to do so doesn’t always exist. For these parties, conditions affecting the poor coating may:Read More
Sometimes problems with conformal coating are too complicated or difficult to repair. This can occur when bubbles develop in the coating during the application process; bubbles cause voids in the coating that defeat its protective, insulating purpose, suggesting the need for removal. Other situations that lead to inadequate coverage, and may favor coating removal, rather than repair include:
- Coating application that’s either too thick or thin for the project’s purposes.
- Component surface finishes that adapt poorly to the conformal material chosen for coverage.
- Disparities in surface tension/surface energy.
- Gravity issues that negatively impact application of liquid coating.
- Improper mixture of two-part materials.
- Inadequate fixturing or placement of assembly components in the coating area.
- Inadequate masking implementation.
- Incorrect interpretation of coating requirements.
- Residue on the coating surface during coating application.
- Poor, uneven coating application.
Overly thick film application or use of coating equipment/materials unsuited to the assignment are major causes of coating problems. In these cases, complete or partial removal of the conformal film from the PCB may be the best solution.
Thus, it is important before beginning any conformal coating assignment for designers and users to recognize the various types of conformal coatings and their interactions with the parts/materials they cover, to protect the products in their respective end-use environments, for the expected design-life of each component.
When removal is the best option for your coating problem, it is advisable to consult prevailing industry standards for appropriate process guidelines. For instance, IPC-7711/7721 delineates recommended procedures for conformal coating removal from, and replacement onto, PCBs. IPC-A-610 is a widely-held standard for electronic assemblies, offering users limited but valuable criteria for conformal coating applications. Designed and constructed with the intent of obtaining maximum confidence in the materials with minimum test redundancy, IPC-CC-830B qualifies the definition, use and conformance of all conformal coatings types for PCBs. In most cases, coating removal is required when assemblies don’t meet the requirements of IPC-CC-830, concerning overall quality conformance of each
The Logistics of Coating Removal
The logistics of coating removal are largely dependent on the type of coating material, its position on the PCB, and the board’s components. Proper identification of the coating material, and the methods used for its original application, are essential to correct determination of the removal method. Once these have been identified, determination of the appropriate removal method can be achieved.
In many cases, chemical strippers can dissolve conformal coatings from PCBs. Acrylic films are typically removed easily by soaking in a solution of stripping fluid, followed by mild mechanical abrasion if necessary. These two processes also work for coatings such as epoxy, silicone and urethane; however, since these substances have higher levels of chemical resistance than acrylic, complete coating removal is more difficult and time-consuming. In all cases, the stripping solution’s compatibility with the PCB’s components needs to be verified to minimize potential damage during the removal process.
Chemical removal does the least damage to PCBs; it is effective for the liquid coatings -- acrylic, epoxy, silicon and urethane. Chemical methods work less well for parylene films, since the substance is chemical inert. Abrasion, laser, mechanical, plasmatic and thermal removal methods are more successful for parylene films; they also work for liquid coatings in many cases.
Recently applied coating is more easily detached from substrate surfaces than older coatings, regardless of the material, unless the coating itself has begun to decay with age. Larger areas of the board respond best to complete submersion in a tank of stripping fluid. Gentle abrasion using a soft bristle brush will also eradicate coatings.
Please remember that the removal of conformal coating generally requires use of exceptionally caustic and potentially dangerous chemicals; the safety of process operators, the product being treated and the immediate environment can be jeopardized by use of inappropriate removal materials and methods. Consultation with a certified conformal coating specialist is highly recommended prior to removing conformal coating. To this end, the professionals at Diamond MT are eminently qualified, and would be glad to be of assistance.
To discover more about conformal coating rework and removal, download our whitepaper now:Read More
Defects to either the PCB assembly or its conformal coating can be sufficient to cause coating removal. Whether repair technologies address the circuit board’s components or the conformal film, subsequent post-repair coating (recoating) processes need to address:Read More
- Conformal coating applied incorrectly can cause PCB malfunction.
- Selecting the wrong coating material from among acrylic, epoxy, parylene, silicone or urethane can be a source of board failure, if it does not support the PCB’s operating environment.
Removing the coating may be necessary if these conditions prevail.Read More
Conformal coatings are designed to protect printed circuit boards (PCBs), assuring they work under all operational circumstances. However, cases emerge where boards fail to function despite conformal coating protection. Such non-performance can be a consequence of:Read More
Not completely understood, electrically conductive tin whiskers are crystalline structures between 1-2 millimeters (mm) that can grow from surfaces where tin is used as a final finish; surfaces finished with electroplated tin are particularly susceptible to whisker growth. Although their occurrence was originally documented during the 1940s, no real solution has yet been devised to prevent their development, which may reach 10 mm in some cases. This is unfortunate because tin whiskers have the capacity for generating arcing and short circuits between electrical elements of printed circuit boards (PCBs) and related electronic equipment.
Tin Whiskers: Their Origin and Impact
Physically, tin whiskers result from the spontaneous growth of tiny, filiform hairs or tendrils upon tin surfaces. These structures can create electrical paths, often within the presence of compressive stress during component operation. Because they usually develop in a functional environment that supports short circuits or arcing, tin whiskers don't need to be airborne to damage electronics. Among other problems, the four main risks with tin whiskers are:
- Stable short circuits in low voltage, high impedance circuits.
- Transient short circuits may develop where tin whiskers span tightly-spaced circuit elements maintained at different electrical potentials.
- Metal vapor arcs result when a whisker-short occurs in a high-current/voltage environment. They are perhaps the most destructive of electronic system failures attributed to tin whiskers.
- Contamination from debris resulting from tin whisker presence can interfere with component performance.
- Behaving like miniature antennas in fast digital circuits or at frequencies above 6 GHz, generating a negative impact on circuit impedance and stimulating reflections.
- Causing failures in relays, a source of deep concern for relay-functions as important as those for nuclear power facilities.
- In outer space (or any vacuum), tin whiskers can short circuit high-power components, ionizing and potentially conducting hundreds of amperes of current, exponentially increasing the short circuit’s damage.
- Tin whiskers have caused malfunction and recall of medical pacemakers.
- Whiskers located in computer disk drives can break, resulting in bearing failures or head crashes.
Conformal Coatings Mitigate the Effects of Tin Whiskers
Selecting a tin whiskers’ mitigation strategy is important; because the source of their growth is unknown, they cannot be entirely eliminated. Although ceramic coatings have proven successful, conformal films made from polymeric compounds such as vapor-deposited parylene, or wet application acrylic and urethane, deflect whiskers away from the coating surface. For instance, studies conducted by NASA seeking tin whisker control for space craft have shown urethane conformal coatings successfully mitigate tin whisker growth. In addition, some acrylic wet coatings, such as HumiSeal 1B31, also mitigate tin whisker’s problems. For various reasons, other conformal coatings -- epoxy, and silicone – are less effective minimizing the development of tin whiskers and their impact on PCB performance.
Perhaps the most effective conformal coating for alleviation of tin whisker related issues is parylene. Deposited in gaseous form, through a chemical vapor deposition (CVD) process, parylene seeps deep into substrate surfaces, penetrating spaces as minute as 0.01mm. In doing so, it forms a pinhole-free protective film that is ultra-thin but exceptionally durable. Chemically inert and of high tensile strength, parylene retains its stability throughout a wide range of temperatures. Because it can be applied at room temperature, parylene application is stress-free. These properties combine to support superior mitigation of tin whiskers.
. However they are applied, conformal coatings create a physical barrier over electronic components that stops tin whisker damage. Conformal coatings:
- Form a protective film that safeguards assembly circuitry and components, physically separating them from each other.
- Substantially diminish tin whiskers bridging between the separated components.
- Lower whiskers’ capacity to generate arcing and shorts.
Tin whiskers can generate arcing and short circuits leading to systemic failures in PCBs and similar electrical assemblies, significantly damaging and otherwise altering their performance expectations. Vital devices, equipment and facilities such as pacemakers, power plants, and even satellites have had their function diminished by the presence of tin whiskers. Determining methods for preventing or slowing tin whisker growth is difficult because:
- outside of some evidence they are the product of mechanically- and thermally-induced stresses,
- the exact mechanism behind their development is not fully understood.
Where they develop, mitigation of tin whiskers is essential to limiting their impact on assembly performance. Conformal compound coatings such as parylene, and to a lesser extent acrylic and urethane, can stop tin whiskers from;
- penetrating an applied protective barrier,
- bridging electrical components and
- creating arcing or a short.
While it is impossible at the moment to completely prevent the occurrence of tin whiskers, their mitigation with conformal coatings will dramatically limit whisker growth and equipment damage. Vapor-deposited parylene and wet coatings such as acrylic and urethane, provide generally good tin whisker defense. Other traditional wet conformal coating materials such as epoxy and silicone are mostly ineffective as protection against the development and effect of tin whiskers.Read More
Protection of printed circuit boards (PCBs) is most often achieved with either potting or conformal coating. The selection of which method to use depends upon the PCB’s purpose and how much protection it requires. Potting offers the strongest shielding barrier, but is also affected by a range of operational disadvantages that can offset its functional benefits. Conformal coatings generate reliable barrier protection, which frequently circumvent the problems inherent in potting. This is particularly the case with parylene, a non-liquid conformal coating.Read More
Understanding the characteristics of various conformal coating types, and their interactions with the extreme range of products and materials to which they are applied, ensures optimal function, performance reliability and product-life. Designers and users of conformal coatings should be aware of the properties of various types of conformal coatings and their interactions with the parts/materials they cover, to protect the products in their respective end-use environments for the expected design-life of each component.Read More
Methods for Measuring Conformal Coating ThicknessRead More
The Workmanship Standards developed by the National Aeronautics and Space Agency (NASA) are essential to assuring reliable performance of the aeronautic, defense and space equipment it uses and monitors.Read More
Acrylic (AR) and polyurethane (UR) conformal coatings are among the best known and most commonly used conformal coating materials. As liquid coatings, both can be applied to substrates through a variety of methods:Read More
How do you ensure that a potential conformal coating provider has the professional credentials and expertise necessary to avoid costly mistakes?Read More
Coating thickness is critical to the proper functioning of your printed wiring assembly, circuit board, or electronic device.Read More
Bubbles and foam are two of the leading causes of failure during conformal coating inspections. Because of this, it’s worth looking at these defects more closely.Read More
Conformal Coatings are polymeric materials used to protect circuitry, parts, and related components. They are most commonly used to protect printed circuit boards (PCBs) and electronic devices.Read More
Once you've decided to use conformal coating for your device, a question that often comes up is:Read More
You've done your research, chosen a conformal coating provider, and coated your device. Now you want to know if the coating properly adhered.Read More
Conformal coatings are a protective, non-conductive dielectric layer that are added to a circuit board or electronic device.Read More
Electronics manufacturers need devices that withstand heat, cold, rain, snow, vibration, fungus, oxidation, and corrosion through decades of operation.Read More
Protective Conformal CoatingsRead More
Conformal CoatingsRead More
Just about every major type of conformal coating provides protection against moisture. If you get a printed circuit board coated with epoxy, acrylic, urethane, silicone or parylene wet, typically all that you have to do is wipe it off. Environments with high humidity pose a different set of challenges. Because moisture is omnipresent in humid environments, the conformal coating doesn't just have to resist water ingress. It also needs to completely seal the coated item. Given this additional requirement, the best choice will usually be either silicone or parylene.Read More
The quality of a conformal coating job is directly related to the cleanliness of the substrate that is being coated. Clean substrates coat well, and contaminated ones don't. The only way to manage the problem is to inspect and clean the board or other item before applying the coating -- once it's coated, it's essentially too late.
Coverage in Undesired Areas
Conformal coatings frequently play a critical role in protecting medical, electronics, defense, aerospace, LED, and automotive applications from contaminants and other potentially hazardous substances. But they're not infallible.
Conformal Coating Selection: Weighing the Pros and Cons for Your Application
So you'd like to know a little something about parylene conformal coating, but were afraid to ask. You need not be ashamed. The process is so fundamental to electronic manufacturing that it can very easily be taken for granted.
Printed circuit boards are extremely susceptible to a wide range of contaminants that can significantly damage or ruin them in a relatively short period of time. These contaminants include moisture, dust, and harmful chemicals. In addition, electronic circuits are also susceptible to extreme temperatures and environments.
Parylene conformal coating is a very robust coating, but sometimes it is not the right fit for a customer’s application for one reason or another. The entire conformal coating process is based on first identifying the standards to be used and customer’s protection desired. It would therefore only make sense that there are alternatives to parylene for different conformal coating demands.
Silicone Conformal Coating
Tags: conformal coating, silicone conformal coating, tin whisker mitigation, urethane conformal coating, type sr conformal coating, Humiseal 1A33, type ur conformal coating, conformal coating consultation
Maintaining proper thickness for silicone conformal coating is critical because it is applied very thick compared to other conformal coatings. If a coating is applied too thick, it may create excessive stresses on solder joints and components (particularly glass-bodied components). If a coating is applied too thin, it may not reach the optimum properties described on the Technical Data Sheet. For this reason, the IPC created the J-STD-001 to regulate and standardize the thickness that coatings are applied at. For silicones, the J-STD-001 calls out 0.00197 to 0.00827 in. Our operators strive to hit between .002” and .008” for silicone applications.
Type AR (acrylic resin) conformal coatings are a popular choice for conformal coating projects because of their moisture protection, low cost, and ease of application. There are many different varieties of type AR conformal coatings such as:
Last week, we discussed what the causes of bubbles in conformal coating are. Now, let’s go through the various ways to remedy the bubbles.
Nexus3C, the Conformal Coating Centre, have arranged a program of workshops and conferences over the next twelve months across North America, Asia and Europe for users of conformal coating.
- HumiSeal 1A33
- HumiSeal 1A20
- Humiseal 1A27
- Humiseal 2A64
- HumiSeal 1A34
- Hysol PC18M
- CONATHANE CE-1155-35
- CONAP CE-1170
- CONATHANE CE-1164
- Techspray Fine-L-Kote
- MG Chemicals 4223
- Electrolube PUC
You should consider using type ur conformal coating whenever your application has any issues with chemical resistivity as type ur coatings are very resistant to chemical solvents. Type ur conformal coating is also smart to include in any tin whisker mitigation strategy, as NASA studies have shown that urethane conformal coatings are one of the few ways to successfully mitigate tin whisker growth. Finally, applications that can see any direct mechanical wear against the coating should consider urethane conformal coatings as well.
Tin whiskers are electrically conductive, crystalline structures of tin that sometimes grow from surfaces where tin (especially electroplated tin) is used as a final finish. They typically grow from lengths of 1-2 millimeters (mm) but have been observed to lengths in excess of 10 mm. They are a serious issue in the electronics world because they have been known to cause short circuits between circuit elements.
Diamond SCH Global Conformal Coating Solution Provider exhibiting at Nepcon Shenzhen next week
NASA-STD 8739.1 is the Workmanship Standard for Polymeric Application on Electronic Assemblies, which describes NASA’s technical requirements, procedures, and documenting requirements for staking, conformal coating, bonding, and encapsulation of printed wiring boards and electronic assemblies. Included are requirements which establish the responsibility for documenting, fabrication, and inspection procedures to be used for NASA work including supplier innovations, special processes, and changes in technology. NASA-STD 8739.1 was initially released in August of 1999, with improvements and minor changes to the standard in recent years. The current up-to-date revision is NASA-STD 8739.1A with Change 2.
Stripping or removal of unwanted conformal coating from a printed circuit board (PCB) can be a relatively simple process or a very messy difficult job. It does depend on several factors including the type of conformal coating you need to remove, where the coating is found and the type of components on the board.
The Conformal Coating Standards that currently exist can be considered from two points of view. First, there are the standards that are used by the manufacturers of conformal coatings to qualify the products, whether that is done by self-certification or completed by independent testing. Second, the standards are a method for users to determine the quality of the conformal coatings they are considering to select.
Conformal Coatings are used regularly in an attempt to cover technology designs on printed circuit boards (PCBs). Normally, this is done by using a pigmented (coloured) conformal coating which obscures the components below the conformal coating material.
Urethane conformal coating is becoming an increasingly popular conformal coating choice. However, it is not suitable for all applications. Instances where the product is going into a high vibration environment or has a high heat requirement would not ideal candidates for urethane conformal coatings.
Diamond-MT has joined the Nexus supplier database which has launched June 1st 2012.
Light emitting diodes (LEDs) are a huge and growing even bigger segment of the electronics industry. LEDs are expanding into environments that demand a higher l evel of protection in order for the LED to function properly. One way to get this level of protection is by using conformal coating.
Silicone conformal coating is becoming an increasingly popular choice for conformal coating applications. Because of its high temperature capabilities, moisture protection, and ease of application/rework, people are strongly considering silicone coatings for their projects.
One potential issue with considering selective conformal coating with a robotic conformal coating system is misaligned components on the PCB which can potentially damage the spray heads which are moving along a set pattern on the board and the components themselves be damaged as they travel. Spray heads are one of the most critical parts on the spray robot. Repairing damage can get costly.
Solvents can be used safely. However, the exposure of the operator to the solvent fumes must be REGULARLY measured and RECORDED. This ensures a safe operating environment and if an OSHA problem does arise in the future, evidence exists to rule out the conformal coating process as the culprit.
Technology varies between the platforms and the valves but essentially they achieve the same result. The goal is to deposit coating where you want it, removing the issue of masking which is required in batch processing with dip or spray booths.
In applications that have an exposure to solvents, acrylic conformal coating is not the best choice. Acrylic conformal coating can be removed with a weaker solvent such as isopropyl alcohol or xylene. Whenever it faces even stronger solvents, it will not offer the protection that is needed, especially if your product is a mission critical device. Other coatings, such as urethane or parylene conformal coating have a far better resistance to solvents than acrylics.
Tags: acrylic conformal coating, parylene conformal coating, conformal coating, silicone conformal coating, conformal coatings, HumiSeal 1B31, urethane conformal coating, HumiSeal, epoxy conformal coating
Medical Conformal Coatings Used
While all conformal coating types can be used for different applications, for many medical devices, parylene is the way to go. Because parylene is biologically inert, FDA approval of parylene coated devices is well-documented. The coatings comply with USP Class VI plastics requirements and are MIL-I-46058C / IPC-CC-830B listed. Another benefit for medical devices such as stents and catheters is that parylene is entirely conformal, meaning that component configurations with sharp edges, points, flat surfaces, crevices or exposed internal surfaces are coated uniformly without voids or pinholes.
Tags: parylene conformal coating, parylene coating process, Diamond-MT, conformal coating, silicone conformal coating, conformal coatings, LED conformal coating, Automotive conformal coatings, Medical conformal coatings, conformal coating standards
One of the different factors to take into account when trying to determine the proper parylene thickness is the amount of clearance needed. If it is a printed circuit board that is an enclosure, there usually will not be too many clearance issues. However, in some cases, even an extra mil of coating can cause extra mechanical abrasion to the parylene which can result in damaged parylene.
WHAT IS CONFORMAL COATING
Conformal coating is a protective non conductive dielectric layer that is applied to protect the assembly from damage due to contamination, salt spray, moisture, fungus, dust and corrosion caused by harsh or extreme environments.
ARE THERE DIFFERENT TYPES OF CONFORMAL COATING?
There are 5 different mediums for conformal coating:
- Acrylic Resin
- Urethane Resin
- Epoxy Resin
- Urethane Resin
WHAT ARE THE BENEFITS OF EACH TYPE OF CONFORMAL COATING?
- Parylene (Type XY)
- Acrylic Resin (Type AR)
- Epoxy (Type ER)
- Polyurethane (Type UR)
- Silicone (Type SR)
Depending on your application, choosing to use conformal coating equipment can be a very wise choice for maximum efficiency. I would recommend use of the conformal coating process decision worksheet to determine your coating needs and whether you should outsource conformal coating prior to purchasing a machine.
Conformal Coating Process – Phase 1 – Prior to Parts Arrival
Once we receive a purchase order from a customer, all of the pertinent information such as drawings, specifications, and special instructions are given to the quality department from our marketing team to create custom work instructions for that particular part. If the material to be used has not yet been determined, we work with the customer to determine the best material for their application.
WHAT ARE TIN WHISKERS
Tin whiskers are electrically conductive, crystalline structures of tin that sometimes grow from surfaces where tin (especially electroplated tin) is used as a final finish. Tin whiskers typically grow from lengths of 1-2 millimeters (mm) but have been observed to lengths in excess of 10 mm. Electronic system failures have been attributed to short circuits caused by tin whiskers that bridge closely-spaced circuit elements maintained at different electrical potentials.
Tags: acrylic conformal coating, Diamond-MT, conformal coating, conformal coating equipment, HumiSeal 1B31, conformal coating methods, conformal coating service, conformal coating removal, conformal coating rework
Parylene Coating Process – Phase 1 – Prior to Parts Arrival
Once we receive a purchase order from a customer, all of the pertinent information such as drawings, specifications, and special instructions are given to the quality department from our marketing team to create custom work instructions for that particular part.
How to get Repeatable Conformal Coating Thickness
Measuring your conformal coating thickness is one thing, however making it a reliable and repeatable thickness is something else all together. There are three main ways of conformal coating application where a repeatable thickness can be obtained, however, a fair degree of training and skills are needed to achieve this.
How to Improve Parylene Adhesion
Parylene, through its deposition process, does not adhere chemically, only mechanically, to any given substrate. In order to improve parylene adhesion to its best possible levels for a wide variety of substrates, different methods of surface modification via adhesion promoters must be used. Adhesion promotion methods are typically used prior to the actual coating process, however some can be integrated during the process itself.
Conformal Coating Process Decision Worksheet
A common objection we receive from potential customers is that they perform conformal coating in-house as opposed to out-sourcing the coating to a vendor. Many factors are often overlooked when it comes to conformal coating, so let's go through a process decision worksheet that takes into account many variables before a final decision is reached.
How to control viscosity with Dip Coating Equipment
The Benefits of Acrylic Conformal Coating
Acrylic conformal coating offers its many benefits as your conformal coating of choice. The main benefits of acrylic conformal coating are the ease of use, physical properties, and their low costs.