FR4 PCB Materia1
FR4 is a commonly used PCB (Printed Circuit Board) substrate, the full name of which is glass fiber reinforced epoxy laminate. It is widely used for its good electrical insulation properties, mechanical strength and flame retardancy.FR4 is commonly used in the production of single, double-sided and multi-layer PCB circuit boards, and is particularly suitable for products with high performance electronic insulation requirements. This material is made of specialized electronic cloth impregnated with epoxy phenolic resin and other materials, and is hot-pressed at high temperatures and pressures.The characteristics of FR4 include stable electrical insulation properties, good flatness, smooth surface, no pits, and standard thickness tolerances. In addition, FR4 has good heat and moisture resistance and good machinability. In the PCB industry, FR4 is considered a cost-effective choice for insulating structural parts in motors and electrical equipment, as well as various circuit board pads and test boards.
FR4 is generally categorized into: FR4 rigid board, common board thickness 0.8-3.2mm FR4 thinness board, common board thickness less than 0.78mm.
FR-4 sheet general technical indicators are: flexural strength, peel strength, thermal shock properties, flame retardant properties, volume resistance coefficient, surface resistance, dielectric constant, dielectric loss angle tangent, glass transition temperature Tg, dimensional stability, the maximum operating temperature, warpage and so on.
PCB material classification
1. Glass cloth substrate: FR4, FR5
By the special electronic cloth impregnated with epoxy phenolic epoxy resin after high temperature, high pressure, hot press from the plate-like compression products.
Epoxy glass fiber cloth substrate (commonly known as: epoxy board, fiberglass board, fiberboard, FR4). Epoxy glass fiber not substrate is a class of substrate with epoxy resin as the binder and electronic grade glass fiber cloth as the reinforcing material.
Epoxy glass fiber cloth copper cladding board high strength, good heat resistance, good dielectric properties, substrate through-hole can be metalized to achieve double-sided multi-layer printing layer and layer circuit conduction, epoxy glass fiber cloth copper cladding board is the most widely used in all qualities of copper cladding boards, the largest amount of a class.
2. Paper substrate: FR1, FR2, FR3, etc.
Phenolic paper substrate is a phenolic resin as a binder, wood pulp fiber cloth as a surface reinforcing material.
3. Composite substrates: CEM-1 and CEM-3
This type of substrate is mainly CEM series copper-clad plate, of which CEM-1 (epoxy paper-based core material) and CEM-3 (epoxy glass nonwoven core material) are two important varieties of CEM. CEM series of boards have good processability, flatness, dimensional stability, thickness accuracy, its mechanical strength, dielectric properties of the water absorption, resistance to metal migration, etc. are higher than the paper substrate, while the mechanical strength (CEM (-3) is about 80% of FR-4, the price is lower than FR-4 board.
4. Special material substrate (ceramic, metal, etc.)
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