Why is PCB use FR4？

Why is PCB use FR4？FR4 is one of the most commonly used materials for PCBs made of a variety of materials.Printed circuit boards (PCBs) are critical components of modern electronics, providing a platform for electronic components to be interconnected and communicate with each other. In this blog, we will explore why PCBs use FR4, its properties and characteristics, as well as its advantages and disadvantages

1.What is PCB use FR4 ?

FR4 is a composite material composed of woven fiberglass cloth and epoxy resin. It is the most commonly used material for PCB substrates due to its excellent electrical, mechanical, and thermal properties. FR4 is also known as glass-reinforced epoxy (GRE), glass fiber-reinforced epoxy laminate (G-10), and fiberglass board.

2.PCB use FR4 Properties and Characteristics

FR4 has several properties and characteristics that make it an ideal material for PCB substrates. These include:

Electrical Properties

FR4 has excellent electrical properties, making it an ideal choice for PCBs. It has a high dielectric constant, which allows it to provide good insulation and reduce signal loss. FR4 also has low electrical losses, high breakdown voltage, and excellent dimensional stability, all of which contribute to its superior electrical performance.

Mechanical Properties

FR4 has excellent mechanical properties, making it a durable and robust material for PCBs. It has high tensile strength, stiffness, and impact resistance, allowing it to withstand harsh environmental conditions and mechanical stresses.

Thermal Properties

FR4 has excellent thermal properties, making it suitable for high-temperature applications. It has a high thermal conductivity, which helps to dissipate heat and maintain stable temperatures. FR4 also has a low coefficient of thermal expansion, meaning it expands and contracts less than other materials when exposed to changes in temperature.

3.Advantages of PCB use FR4

There are several advantages of using FR4 in PCBs, including:

Cost-Effective

FR4 is a cost-effective material for PCB substrates, making it a popular choice for both hobbyists and commercial manufacturers. Suppliers readily offer it in large quantities at a reasonable price.

Easy to Work With

FR4 is easy to work with, allowing for easy fabrication and assembly of PCBs. You can easily cut and drill it, and mount components onto the substrate with ease

High Performance

FR4 has excellent electrical, mechanical, and thermal properties, making it an ideal material for high-performance PCBs. It provides good insulation, reduces signal loss, and can withstand harsh environmental conditions and mechanical stresses.

Good Compatibility with Manufacturing Processes

FR4 is compatible with a variety of manufacturing processes, including through-hole mounting and surface-mount technology. Its versatility makes it suitable for a wide range of PCB applications.

Disadvantages of PCB use FR4

While there are several advantages to using FR4 in PCBs, there are also some disadvantages, including:

Limited Temperature Range

While FR4 has good thermal properties, it has a limited temperature range compared to other materials, such as ceramic or metal substrates. FR4 can typically withstand temperatures up to around 130-140°C, making it unsuitable for high-temperature applications.

Limited Signal Integrity

While FR4 provides good insulation and reduces signal loss, it has limited signal integrity compared to other materials, such as Rogers or Teflon. This can result in reduced performance for high-frequency or high-speed applications.

Limited Flexibility

FR4 is a rigid material, making it unsuitable for flexible or bendable PCB applications.If you require flexibility, consider using alternative materials such as polyimide or polyester