What is FR4 Material in PCB and its advantages?
In this article, we are going to discuss about what is FR4 Material in PCB and its advantages?
FR4- Material in Details
FR4 is a standard for PCB manufacturing, which are belong to the NEMA (National Electrical Manufacturers Association) that is made of a glass-reinforced epoxy resin laminate.
FR means “flame retardant” which are under the UL94V-0 standard on plastic material inflammability. The 94V-0 code can be found on all FR-4 PCBs. That is giving the guarantees the non-propagation of fire and its rapid extinguishing when the material burns.
FR-4 is a glass transition (TG) is of the order of 115°C to 200°C for the High TGs that is depending on the manufacturing methods and the resins used. Generally FR-4 PCB will have a layer of FR-4 sandwiched between two thin layers of laminated copper.
General FR4: its name indicates, this is the standard FR-4 with heat resistance of the order of 140°C to 150°C.
High TG FR4: this type of FR-4 has higher glass transition (TG) of around 180°C.
High CTI FR4: Comparative Tracking Index higher than 600 Volts.
FR4 with no laminated copper: ideal for insulation plates and board supports.
There are more details of the characteristics of these different materials later in the article.
Types of FR-4
FR4 SHENGYI family S1000H - Thickness from 0.2 to 3.2 mm.
FR4 VENTEC family VT 481 - Thickness from 0.2 to 3.2 mm.
FR4 High TG
FR4 SHENGYI family S1000-2 - Thickness from 0.6 to 3.2 mm.
FR4 VENTEC family VT 47 - Thickness from 0.6 to 3.2 mm.
FR4 High IRC
FR4 SHENGYI family S1600 - Standard thickness 1.6 mm.
FR4 VENTEC family VT 42C - Standard thickness 1.6 mm.
FR4 with no copper
This material is an epoxy glass with no copper, designed for use in insulation plates, templates, board supports, etc. They are manufactured using Gerber type mechanical drawings or DXF files - Thickness from 0.3 to 5 mm.
Advantage of FR4
FR4 has the advantage of having a good resistance-weight ratio. It does not absorb water, keeps high mechanical strength and has a good insulating capacity in dry or humid environments. It has cheap cost to make them a standard option for the production of small series of PCBs or for electronic prototyping.
The most commonly used insulating base material for PCB’s. FR4 is made from woven glass fibers which are bonded together with an epoxy. The board is cured using a combination of temperature & pressure which causes the glass fibers to melt & bond together, thereby giving the board strength & rigidity. The first 2 characters stand for “Flame Retardant”. FR4 is technically a form of fiberglass, & some people do refer to these composites as fiberglass boards/fiberglass substrates, but not often.