FR4 Material PCB-All you need to know about flame retardant circuit board

If you are here, you are probably already familiar with Printed Circuit Boards (PCBs). Modern electronics consider those boards an essential component. The PCBs enable electronic components to connect and communicate with each other through lines of wires.

Determining the right material for a PCB is crucial in determining the board’s performance, durability, and functionality. The most common and well-used material for PCBs is FR4. FR4 is a type of fiberglass epoxy laminate material.

In this article, we will examine FR4, its properties and unique abilities, and the reasons for its widespread use in PCBs.

FR4 is not the only material available, so we will also compare other materials to understand which one suits the best for your application.

What is FR4?

FR4 is a type of fiberglass-reinforced epoxy laminate. It is a type of composite material consisting of layers of fiberglass cloth clogged together with an epoxy resin binder.

This type of material provides extreme mechanical strength, while epoxy resin provides insulation and protection from moisture and different type of environmental factors.

PCB manufacturers widely use FR4 material due to its excellent electrical, mechanical, and thermal properties. For new PCB designs, it is recommended to use FR4 most often. The material can handle both simple and complex PCB designs as one.

When you order PCB or PCBA, you will often be provided with FR4 as the first option. This material is very common and recommended among new designs. If you have any doubt regarding the PCB material you should use, FR4 might be your right choice.

Properties and strengths of FR4 PCB material

FR4 has many properties and strengths that make it an ideal material for PCB manufacturing. Here are some of the most important properties of FR4:

1. High Tensile Strength – The FR4 has a high tensile strength. This type of strength makes it extremely suitable for use in PCBs that require mechanical stability. The high tensile strength is especially useful for use in high-stress applications.
2. Low Water Absorption – FR4 has a low water absorption rate. What it means is basically it has the ability to resist moisture and humidity. This is extremely useful in high-humidity environments or outdoor and industrial applications.
3. Thermal Stability – FR4 is known to be the best material for thermal stability. It can resist high temperatures without losing its material quality. For applications such as power supplies, this is crucial. Power supplies PCB circuits can often overheat.
4. Electrical Insulation – Brilliant isolation which can prevent electrical currents from flowing between different layers of the PCB. By avoiding this, we can eliminate most causes of short circuits and other electrical problems.
5. Last but not least, the ability to have great chemical Resistance. The FR4 PCB material is known for its good chemical resistance. It has the ability to resist exposure to chemicals such as acids and bases. It comes very in handy in industrial applications and outdoor use as well.

Why do PCB manufacturers commonly use FR4 in their boards?

Referring to the paragraph above – it’s mostly due to its strengths and properties. FR4 is a very popular choice for printed circuit board manufacturing due to its excellent electrical, mechanical, and thermal properties. Its cost-effectiveness is one of the main reasons why PCB manufacturers commonly use FR4 in their boards. It is much cheaper than other materials used in PCB manufacturing, such as ceramic or Teflon. FR4 is also widely available and can be easily sourced from many PCB manufacturers.

When you are looking to produce your PCB board you might look at different factors. Factors such as price, quality, and speed of manufacturing play an important role. FR4 answers all the above and enables designers to get the highest quality at the lowest cost.

Another reason FR4 is so commonly used in PCBs is its excellent electrical properties. FR4 has a low dielectric constant and low dissipation factor, which means it can maintain a stable signal and minimize signal loss. Its high insulation resistance and breakdown voltage also make it ideal for high-voltage applications.

When we use a certain material we want to make sure it suits our application. For FR4, most of its abilities related to electrical properties can fulfill the needs of most common designs.

FR4 is also mechanically stable, with a high strength-to-weight ratio. It can withstand mechanical stress, vibration, and thermal shock, making it suitable for a wide range of applications. FR4’s thermal properties are also excellent, as it has a low coefficient of thermal expansion and can withstand high temperatures without degrading.

These are the main reasons why This type of PCB material is most commonly used. When you are about to choose the material for your application, you should refer to this paragraph to verify if the material can fulfill your needs.

When you should use FR4 in your application?

FR4 is a versatile material that is suitable for a wide range of PCB applications. Here are some situations where you should consider using FR4 for your PCB:

1. Low to Medium Frequency Applications – FR4 is an ideal material for low to medium-frequency applications. This is due to its excellent electrical insulation and low-loss tangent. Applications such as consumer electronics, automotive electronics, and industrial controls commonly use them.
   
   
2. Cost-Sensitive Applications – Compared to other materials, FR4 is a cost-effective option. Ceramic or Teflon materials are considered expensive in comparison. If your product has a price budget, you should consider FR4 as your choice to go.
   
   
3. High-Temperature Applications – FR4 has excellent thermal stability. It can resist high temperatures without degrading. Most applications will benefit from such properties and abilities.
   
   
4. High Mechanical Stress Applications – FR4 has a high mechanical strength. if your PCB designs are located in stressful environments such as a car or industrial machine, FR4 might be a good choice for PCB fabrication.
   
   
5. General-Purpose Applications – Due to its versatility, FR4 is widely used as a material in various applications. It is an ideal material for applications such as power supplies, lighting, and control systems. IoT systems, smart homes, and other small wireless controllers are great choices as well.

Comparing FR4 to other materials

PCB manufacturers commonly use FR4 as a material, but it’s not the only material available. Each material used in PCB manufacturing possesses its own set of properties and advantages. Let’s take a look at how FR4 compares to other materials used in PCB manufacturing.

1. Ceramic PCBs – Ceramic PCBs are a popular choice for high-temperature applications due to their excellent thermal conductivity and mechanical strength. However, ceramic PCBs are more expensive to manufacture than FR4 PCBs and are not as widely available.
   
   
2. Teflon PCBs – Teflon PCBs are a popular choice for high-frequency applications due to their low dielectric constant and low loss tangent. However, Teflon PCBs are more expensive to manufacture than FR4 PCBs and are not as widely available.
   
   
3. Aluminum PCBs – Aluminum PCBs are a popular choice for LED applications due to their excellent thermal conductivity. However, aluminum PCBs are more expensive to manufacture than FR4 PCBs and are not suitable for applications that require high mechanical strength.
   
   
4. Flexible PCBs – Flexible PCBs are a popular choice for applications that require a flexible form factor. However, flexible PCBs are more expensive to manufacture than FR4 PCBs and are not suitable for applications that require high mechanical strength.

Summary

If you read this far – you are probably an expert in FR4 PCB material. Whenever you have a doubt about which material to use for your next project, we at PCBasic are here for you. PCBasic specializes in all types of PCB materials and fabrication methods.

With years of experience, we accumulated the necessary knowledge, skills, and tools to help you manufacture from a prototype stage all the way to mass production!

By uploading the Gerber files to our quotation system, we can recommend the most suitable material for your design. Do not hesitate to contact us and receive an instant quote for your next project.