What is FR4?
FR4 is a standard rating and name applied to fiberglass-reinforced epoxy-laminated sheets used in printed circuit board manufacturing. The FR4 rating serves as a grade to indicate the base quality of a laminate sheet, with a variety of materials and designs falling under this category.
The term “FR” represents the material’s flame retardant properties, while the number “4” differentiates it from other materials in the same class.
FR4 is a composite structure consisting of a fiberglass layer at its core. This provides structural stability and a flame-resistant epoxy resin surrounding and binding the fiberglass layer. This resin gives FR4 its rigidity and other physical properties. FR4 sheets are a popular choice among electrical engineers and designers due to their low cost and versatility, high dielectric strength, strength-to-weight ratio, resistance to moisture, and relative temperature resistance, allowing them to perform well in various environmental conditions.
Applications of FR4
PCBs: FR4 sheets are widely popular among electrical engineers and designers as a PCB base material due to its low cost, versatility, and beneficial physical properties, such as high dielectric strength, strength-to-weight ratio, resistance to moisture, and relative temperature resistance.
Insulators: FR4 is used as an insulator for electrical and electronic applications, including transformers, motors, generators, and electronic equipment.
Structural components: FR4 laminates are used in the manufacturing of structural components such as beams, panels, and frames for aircraft, automotive, and marine applications.
Consumer electronics: FR4 is used in the manufacturing of consumer electronics such as smartphones, laptops, tablets, and gaming consoles.
Industrial equipment: FR4 is used in the manufacturing of industrial equipment such as control panels, switches, relays, and sensors.
Aerospace: FR4 is used in the manufacturing of parts and components for aerospace applications such as satellites, rockets, and aircraft.