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FR4 PCB-introduction of the common PCB and material


PCB is the mother of electronic products, an important electrical connection support and the carrier of electronic components. FR4 PCB is a circuit board made of FR4 material, and it is also the most commonly used PCB at present. This article will introduce the types and advantages and disadvantages of FR4 material and FE4 PCB one by one, as well as the manufacturing and assembly of FR4 PCB.

What is FR4 PCB?

FR4, a type of PCB base material, is constructed out of flame-retardant glass fibre and an epoxy resin. These two components are bonded together using an epoxy. If a product has a label that says it is “flame retardant” (often abbreviated as “FR”), then this indicates that it has been tested in accordance with the UL94V-0 standard and determined to be in compliance with it.

Because it adheres well to copper and takes up less water, FR4 is an excellent option for applications that call for a material that can conform to a variety of different shapes and sizes, such as those that use copper foil. Because of this, it is an excellent option to consider for usage in applications that involve copper foil.

For both single sided PCB and double-layer PCB, copper-coated FR4 is the material of choice (PCB). However, FR4 serves as both the prepreg and the core for multilayer boards.

What is FR4 PCB material?

what are the FR4 material properties?

FR4 is used in many electronic products due to its thermal, mechanical, and electrical qualities. Due to their long lifespan and high level of protection, numerous industries are dependent on flame-resistant laminates and prepregs. Electrical conductivity can be found in the FR4 components. Signal integrity and impedance are both impacted by the inherent electrical properties of the PCB material.

They provide information regarding the electrical signal’s speed as well as its capacity to store charge. The hygroscopicity of FR4 is a feature that is necessary for many applications. This percentage reflects the increase in weight of the circuit board substrate that has occurred as a direct result of water absorption. Less than 0.10 percent of water is absorbed by FR4 in a period of 24 hours.

What is the color of FR4 material?

Although FR-4 can be made in a variety of colours, the green variant is by far the most prevalent. On the other hand, it can also be made in yellow, black, and blue variations throughout the manufacturing process.

What are the type of FR4 PCB?

FR4 PCBs can be fabricated into a wide variety of distinct forms. Some of these forms include:
● Single-Sided FR4 PCB
● Double-Sided FR4 PCB
● Multilayer FR4 PCB
● Rigid FR4 PCB
● Flex FR4 PCB
● Rigid-Flex FR4 PCB

Whats the advantage and disadvantage of FR4 PCB?

Advantages: Whats-the-advantage-and-disadvantage-of-FR4-PCBFR4 PCB is easy to get your hands on, not to mention cheap, and it performs admirably in a wide variety of conditions. The high dielectric strength Of FR4 PCB makes it useful as both an electrical insulator and a force processor. Keeping weight down maximises the strength-to-weight ratio. Almost no current is lost electrically.

The low moisture absorption rate of FR-4 PCB makes it a good choice for use in marine environments. The typical TG for FR4 PCB is between 130 and 140 degrees Celsius. Materials with a higher TG are more resistant to heat and humidity (greater than 170 degrees Celsius).

Disadvantages: There are limitations placed on the use of FR-4 PCB in relation to the application of heat, electricity, and voltage. Using FR-4 to insulate copper layers and stop current leakage is a standard practise that has become widespread.

When heated above its safe operating temperature, FR-4 loses some of its dielectric qualities and becomes more conductive. This happens because the material becomes more conductive. It is not advised to utilise FR4 PCBs in high-temperature environments such as aeroplanes.

What’s the application of FR4 PCB?

Fabricating the most popular form of the dielectric material known as FR4 is one of the most common uses for this chemical when making circuit boards. This material is used in multilayered, single sided, double-sided, and dual-sided boards. It’s possible for it to be both single- and double-sided at the same time.

How is FR4 PCB made?

How-is-FR4-PCB-madeThe production of FR4 PCB is a process that requires many processes and requires mutual cooperation. The quality of the product in the previous process will directly affect the production of the next process, and even directly affect the quality of the final product. Therefore, the quality control of key processes plays a particularly critical role in the quality of the final product.The rough production steps of FR4 PCB are as follows:

●Inner dry film
●Brown oxide
PCB Drilling
●Immersion copper plate plating
●Outer dry film
●Outer pattern plating, SES
Solder mask
●Screen printing
●Surface finishing
●Open/Short test
●Final inspection, random inspection, packaging

How thick is FR4 PCB?

The standard thickness of a printed circuit board is 1.57mm. Beyond the standard range of 0.78 mm to 2.36 mm, some manufacturers offer bespoke thicknesses. The typical thickness of FR4 PCB is measured against the standard of 1.57 mm. FR4 PCB of arbitrary thicknesses are possible thanks to the ability to combine core and prepreg laminate thicknesses.

What is the difference between FR1 and FR4 PCB?

The difference between FR1 and FR4 PCB is essentially caused by the difference in substrate material.The differing composition of the layers of FR4 PCBs makes it more resistant to heat than FR1/XPC. Fiberglass epoxy laminate is used to create FR4 PCBs. The thickness of a PCB is 1.60mm (0.062in).

The glass fibre of FR4 is layered eight times.FR4 PCB maximum ambient temperature is between 120 ø and 130 ø C, depending on thickness. FR4 is the most widely used PCB base material as it can be fabricated from single to multi-layer PCBs.

FR-1 is made of kraft paper impregnated with phenolic resin and pressed together. FR1 is usually used for single sided PCB as it is not good for through hole technology.

What is the FR4 PCB Assembly Process?

PCB assembly (PCBA) is the process of producing printed circuit boards and placing components. This is a manufacturing technology that converts raw materials into PCB motherboards and finished products for electronic products. It is used in many industries including medical, new energy, military and aerospace.FR4 PCB assembly process is generally divided into PCB design and assembly, packaging. Below are the detailed process steps for reference.

Prepare the circuit board to the production line, place the solder paste, and place the electronic components through the SMT placement machine. After the reflow oven to fix the soldering, the AOI inspection is completed, and then the through-hole and wave soldering are carried out to establish electrical connections in the solder pads and component leads.

After all soldering processes are completed, cleaning and various tests are performed. If you want to learn more about the more specific assembly process, you can browse other articles on PCBA and SMT PCB process on this website.
The detailed steps can be seen below the picture of the detailed assembly steps of the IBE PCBA manufacturer, the picture is:PCB-assembly-process

IBE- one-stop FR4 PCB assembly manufacturer

IBE Electronics Co., Ltd. is an one-stop PCBA Manufacturer that was established in 2005. The PCBA service includes from PCB design, PCB prototyping, PCBA processing (including SMT and DIP ), PCBA testing, and PCBA product assembly and packaging out of the warehouse. IBE has 14 SMT lines, 6 Dip lines, Lab, 75000 m²factory, and 4 product assembly production workshop, which will save your time and cost. Therefore, IBE is a good choice as a FR4 PCB design and assembly manufacturer.


Hopefully through this article you can learn more about FR4 PCB. In addition, FR4 PCB is only one of the many types of PCBs, others include ceramic PCB, aluminum PCB, copper PCB and other material PCBs, as well as 2-layer PCB, multilayer PCB and so on. Please visit our website to learn more about PCB and PCBA.



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