Differences between FR4 and FR5 fiberglass laminates

2024-06-25 14:33 | By: ZTELEC-www.ztelecgroup.com | 81click

FR4 and FR5 are both types of fiberglass-reinforced epoxy laminate materials used in the construction of printed circuit boards (PCBs), but they have some key differences:

FR4_04

FR5

Composition:

FR4: Made of woven fiberglass cloth impregnated with an epoxy resin, with a Tg (glass transition temperature) rating indicated by the “4” in FR4.

FR5: Similar to FR4 in composition but typically has a higher Tg rating1.

Glass Transition Temperature (Tg):

FR4: Generally has a Tg rating around 130-140°C, which is the temperature at which the material transitions from a rigid to a more flexible state.

FR5: Has a higher Tg rating, often around 150-170°C or even higher, making it suitable for applications requiring higher-temperature operation or processing.

Temperature Resistance:

FR4: Suitable for standard electronic applications with moderate

operating temperatures.

FR5: Chosen for applications where higher temperature resistance is necessary, such as high-frequency and high-speed communication devices, military applications, and other specialized electronics.

FR4

FR5

Applications:

FR4 and FR5 are both flame-retardant glass epoxy laminate materials used in the construction of printed circuit boards (PCBs), but they differ mainly in their glass transition temperature (Tg) and their applications due to differing thermal properties:

FR4:

Has a Tg rating around 130-140°C.

Suitable for standard electronic applications with moderate operating temperatures.

Most common and widely used PCB material.

FR5:

Features a higher Tg rating, often around 150-170°C or even higher2.

Chosen for applications requiring higher temperature resistance, such as high-frequency and high-speed communication devices, military applications, and other specialized electronics.

FR5 offers better heat resistance and a higher Tg rating, making it suitable for more demanding environments, while FR4 is the standard choice for a broad range of applications. When selecting between the two, considerations such as operating temperature, mechanical strength, and cost are important factors

FR4: The most common PCB material, used in a broad range of applications including consumer electronics, industrial electronics, and general-purpose PCBs.

FR5: Often selected for more demanding applications that require higher thermal performance.

When choosing between FR4 and FR5, factors like operating temperature, mechanical strength, and cost considerations should be taken into account. The choice depends on the requirements and specifications of the electronic device being designed.